String.CompareTo Method
Important
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CompareTo(Object) |
Compares this instance with a specified Object and indicates whether this instance precedes, follows, or appears in the same position in the sort order as the specified Object. |
CompareTo(String) |
Compares this instance with a specified String object and indicates whether this instance precedes, follows, or appears in the same position in the sort order as the specified string. |
Both overloads of the CompareTo method perform culture-sensitive and case-sensitive comparison. You cannot use this method to perform culture-insensitive or ordinal comparisons. For code clarity, we recommend that you avoid the CompareTo method and call the Compare method instead.
- Source:
- String.Comparison.cs
- Source:
- String.Comparison.cs
- Source:
- String.Comparison.cs
public:
virtual int CompareTo(System::Object ^ value);
public int CompareTo (object? value);
public int CompareTo (object value);
abstract member CompareTo : obj -> int
override this.CompareTo : obj -> int
Public Function CompareTo (value As Object) As Integer
Parameters
Returns
A 32-bit signed integer that indicates whether this instance precedes, follows, or appears in the same position in the sort order as the value
parameter.
Value | Condition |
---|---|
Less than zero | This instance precedes value .
|
Zero | This instance has the same position in the sort order as value .
|
Greater than zero | This instance follows value .
-or-
|
Implements
Exceptions
value
is not a String.
Examples
The following example uses the CompareTo method with an Object. Because it attempts to compare a String instance to a TestClass
object, the method throws an ArgumentException.
using namespace System;
public ref class TestClass{};
int main()
{
TestClass^ test = gcnew TestClass;
array<Object^>^ objectsToCompare = { test, test->ToString(), 123,
(123).ToString(), "some text",
"Some Text" };
String^ s = "some text";
for each (Object^ objectToCompare in objectsToCompare) {
try {
Int32 i = s->CompareTo(objectToCompare);
Console::WriteLine("Comparing '{0}' with '{1}': {2}",
s, objectToCompare, i);
}
catch (ArgumentException^ e) {
Console::WriteLine("Bad argument: {0} (type {1})",
objectToCompare,
objectToCompare->GetType()->Name);
}
}
}
// The example displays the following output:
// Bad argument: TestClass (type TestClass)
// Comparing 'some text' with 'TestClass': -1
// Bad argument: 123 (type Int32)
// Comparing 'some text' with '123': 1
// Comparing 'some text' with 'some text': 0
// Comparing 'some text' with 'Some Text': -1
using System;
public class TestClass
{}
public class Example
{
public static void Main()
{
var test = new TestClass();
Object[] objectsToCompare = { test, test.ToString(), 123,
123.ToString(), "some text",
"Some Text" };
string s = "some text";
foreach (var objectToCompare in objectsToCompare) {
try {
int i = s.CompareTo(objectToCompare);
Console.WriteLine("Comparing '{0}' with '{1}': {2}",
s, objectToCompare, i);
}
catch (ArgumentException) {
Console.WriteLine("Bad argument: {0} (type {1})",
objectToCompare,
objectToCompare.GetType().Name);
}
}
}
}
// The example displays the following output:
// Bad argument: TestClass (type TestClass)
// Comparing 'some text' with 'TestClass': -1
// Bad argument: 123 (type Int32)
// Comparing 'some text' with '123': 1
// Comparing 'some text' with 'some text': 0
// Comparing 'some text' with 'Some Text': -1
open System
type TestClass() = class end
let test = TestClass()
let objectsToCompare: obj list =
[ test; string test; 123
string 123; "some text"
"Some Text" ]
let s = "some text"
for objectToCompare in objectsToCompare do
try
let i = s.CompareTo objectToCompare
printfn $"Comparing '{s}' with '{objectToCompare}': {i}"
with :? ArgumentException ->
printfn $"Bad argument: {objectToCompare} (type {objectToCompare.GetType().Name})"
// The example displays the following output:
// Bad argument: TestClass (type TestClass)
// Comparing 'some text' with 'TestClass': -1
// Bad argument: 123 (type Int32)
// Comparing 'some text' with '123': 1
// Comparing 'some text' with 'some text': 0
// Comparing 'some text' with 'Some Text': -1
Public Class TestClass
End Class
Public Class Example
Public Shared Sub Main()
Dim test As New TestClass()
Dim objectsToCompare() As Object = { test, test.ToString(), 123,
123.ToString(), "some text",
"Some Text" }
Dim s As String = "some text"
For Each objectToCompare In objectsToCompare
Try
Dim i As Integer = s.CompareTo(objectToCompare)
Console.WriteLine("Comparing '{0}' with '{1}': {2}",
s, objectToCompare, i)
Catch e As ArgumentException
Console.WriteLine("Bad argument: {0} (type {1})",
objectToCompare,
objectToCompare.GetType().Name)
End Try
Next
End Sub
End Class
' The example displays the following output:
' Bad argument: TestClass (type TestClass)
' Comparing 'some text' with 'TestClass': -1
' Bad argument: 123 (type Int32)
' Comparing 'some text' with '123': 1
' Comparing 'some text' with 'some text': 0
' Comparing 'some text' with 'Some Text': -1
Remarks
value
must be a String object.
Caution
The CompareTo method was designed primarily for use in sorting or alphabetizing operations. It should not be used when the primary purpose of the method call is to determine whether two strings are equivalent. To determine whether two strings are equivalent, call the Equals method.
This method performs a word (case-sensitive and culture-sensitive) comparison using the current culture. For more information about word, string, and ordinal sorts, see System.Globalization.CompareOptions.
For more information about the behavior of this method, see the Remarks section of the String.Compare(String, String) method.
Notes to Callers
Character sets include ignorable characters. The CompareTo(Object) method does not consider such characters when it performs a culture-sensitive comparison. For example, if the following code is run on the .NET Framework 4 or later, a comparison of "animal" with "ani-mal" (using a soft hyphen, or U+00AD) indicates that the two strings are equivalent.
using System;
public class Example
{
public static void Main()
{
string s1 = "ani\u00ADmal";
object o1 = "animal";
Console.WriteLine("Comparison of '{0}' and '{1}': {2}",
s1, o1, s1.CompareTo(o1));
}
}
// The example displays the following output:
// Comparison of 'ani-mal' and 'animal': 0
let s1 = "ani\u00ADmal"
let o1: obj = "animal"
printfn $"Comparison of '{s1}' and '{o1}': {s1.CompareTo o1}"
// The example displays the following output:
// Comparison of 'ani-mal' and 'animal': 0
Module Example
Public Sub Main()
Dim s1 As String = "ani" + ChrW(&h00AD) + "mal"
Dim o1 As Object = "animal"
Console.WriteLine("Comparison of '{0}' and '{1}': {2}",
s1, o1, s1.CompareTo(o1))
End Sub
End Module
' The example displays the following output:
' Comparison of 'ani-mal' and 'animal': 0
To recognize ignorable characters in a string comparison, call the CompareOrdinal(String, String) method.
See also
Applies to
.NET 9 and other versions
Product | Versions |
---|---|
.NET | Core 2.0, Core 2.1, Core 2.2, Core 3.0, Core 3.1, 5, 6, 7, 8, 9 |
.NET Framework | 1.1, 2.0, 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1 |
.NET Standard | 2.0, 2.1 |
- Source:
- String.Comparison.cs
- Source:
- String.Comparison.cs
- Source:
- String.Comparison.cs
Compares this instance with a specified String object and indicates whether this instance precedes, follows, or appears in the same position in the sort order as the specified string.
public:
virtual int CompareTo(System::String ^ strB);
public:
int CompareTo(System::String ^ strB);
public int CompareTo (string strB);
public int CompareTo (string? strB);
abstract member CompareTo : string -> int
override this.CompareTo : string -> int
member this.CompareTo : string -> int
Public Function CompareTo (strB As String) As Integer
Parameters
- strB
- String
The string to compare with this instance.
Returns
A 32-bit signed integer that indicates whether this instance precedes, follows, or appears in the same position in the sort order as the strB
parameter.
Value | Condition |
---|---|
Less than zero | This instance precedes strB .
|
Zero | This instance has the same position in the sort order as strB .
|
Greater than zero | This instance follows strB .
-or-
|
Implements
Examples
The following example uses the CompareTo method to compare the current string instance with another string.
using namespace System;
String^ CompareStrings(String^ str1, String^ str2)
{
// compare the values, using the CompareTo method on the first string
int cmpVal = str1->CompareTo(str2);
if (cmpVal == 0)
// the values are the same
return "The strings occur in the same position in the sort order.";
else if (cmpVal < 0)
return "The first string precedes the second in the sort order.";
else
return "The first string follows the second in the sort order.";
}
int main()
{
String^ strFirst = "Goodbye";
String^ strSecond = "Hello";
String^ strThird = "a small String*";
String^ strFourth = "goodbye";
// Compare a string to itself.
Console::WriteLine(CompareStrings(strFirst, strFirst));
Console::WriteLine(CompareStrings(strFirst, strSecond));
Console::WriteLine(CompareStrings(strFirst, strThird));
// Compare a string to another string that varies only by case.
Console::WriteLine(CompareStrings(strFirst, strFourth));
Console::WriteLine(CompareStrings(strFourth, strFirst));
}
// The example displays the following output:
// The strings occur in the same position in the sort order.
// The first string precedes the second in the sort order.
// The first string follows the second in the sort order.
// The first string follows the second in the sort order.
// The first string precedes the second in the sort order.
using System;
public class Example
{
public static void Main()
{
string strFirst = "Goodbye";
string strSecond = "Hello";
string strThird = "a small string";
string strFourth = "goodbye";
// Compare a string to itself.
Console.WriteLine(CompareStrings(strFirst, strFirst));
Console.WriteLine(CompareStrings(strFirst, strSecond));
Console.WriteLine(CompareStrings(strFirst, strThird));
// Compare a string to another string that varies only by case.
Console.WriteLine(CompareStrings(strFirst, strFourth));
Console.WriteLine(CompareStrings(strFourth, strFirst));
}
private static string CompareStrings( string str1, string str2 )
{
// Compare the values, using the CompareTo method on the first string.
int cmpVal = str1.CompareTo(str2);
if (cmpVal == 0) // The strings are the same.
return "The strings occur in the same position in the sort order.";
else if (cmpVal < 0)
return "The first string precedes the second in the sort order.";
else
return "The first string follows the second in the sort order.";
}
}
// The example displays the following output:
// The strings occur in the same position in the sort order.
// The first string precedes the second in the sort order.
// The first string follows the second in the sort order.
// The first string follows the second in the sort order.
// The first string precedes the second in the sort order.
let strFirst = "Goodbye"
let strSecond = "Hello"
let strThird = "a small string"
let strFourth = "goodbye"
let compareStrings (str1: string) str2 =
// Compare the values, using the CompareTo method on the first string.
match str1.CompareTo str2 with
| 0 -> // The strings are the same.
"The strings occur in the same position in the sort order."
| x when x < 0 ->
"The first string precedes the second in the sort order."
| _ ->
"The first string follows the second in the sort order."
// Compare a string to itself.
printfn $"{compareStrings strFirst strFirst}"
printfn $"{compareStrings strFirst strSecond}"
printfn $"{compareStrings strFirst strThird}"
// Compare a string to another string that varies only by case.
printfn $"{compareStrings strFirst strFourth}"
printfn $"{compareStrings strFourth strFirst}"
// The example displays the following output:
// The strings occur in the same position in the sort order.
// The first string precedes the second in the sort order.
// The first string follows the second in the sort order.
// The first string follows the second in the sort order.
// The first string precedes the second in the sort order.
Public Module Example
Public Sub Main()
Dim strFirst As String = "Goodbye"
Dim strSecond As String = "Hello"
Dim strThird As String = "a small string"
Dim strFourth As String = "goodbye"
' Compare a string to itself.
Console.WriteLine(CompareStrings(strFirst, strFirst))
Console.WriteLine(CompareStrings(strFirst, strSecond))
Console.WriteLine(CompareStrings(strFirst, strThird))
' Compare a string to another string that varies only by case.
Console.WriteLine(CompareStrings(strFirst, strFourth))
Console.WriteLine(CompareStrings(strFourth, strFirst))
End Sub
Private Function CompareStrings(str1 As String, str2 As String) As String
Dim cmpVal As Integer = str1.CompareTo(str2)
If cmpVal = 0 Then
' The values are the same.
Return "The strings occur in the same position in the sort order."
ElseIf cmpVal < 0 Then
Return "The first string precedes the second in the sort order."
Else
Return "The first string follows the second in the sort order."
End If
End Function
End Module
' This example displays the following output:
' The strings occur in the same position in the sort order.
' The strings occur in the same position in the sort order.
' The first string precedes the second in the sort order.
' The first string follows the second in the sort order.
' The first string follows the second in the sort order.
' The first string precedes the second in the sort order.
The following example demonstrates generic and non-generic versions of the CompareTo method for several value and reference types.
// This example demonstrates the two versions of the
// CompareTo method for several base types.
// The general version takes a parameter of type Object, while the specific
// version takes a type-specific parameter, such as Boolean, Int32, or Double.
using namespace System;
void Show( String^ caption, Object^ var1, Object^ var2, int resultGeneric, int resultNonGeneric )
{
String^ relation;
Console::Write( caption );
if ( resultGeneric == resultNonGeneric )
{
if ( resultGeneric < 0 )
relation = "less than";
else
if ( resultGeneric > 0 )
relation = "greater than";
else
relation = "equal to";
Console::WriteLine( "{0} is {1} {2}", var1, relation, var2 );
}
// The following condition will never occur because the generic and non-generic
// CompareTo methods are equivalent.
else
{
Console::WriteLine( "Generic CompareTo = {0}; non-generic CompareTo = {1}", resultGeneric, resultNonGeneric );
}
}
int main()
{
String^ nl = Environment::NewLine;
String^ msg = "{0}The following is the result of using the generic and non-generic{0}"
"versions of the CompareTo method for several base types:{0}";
Object^ obj; // An Object used to insure CompareTo(Object) is called.
DateTime now = DateTime::Now;
// Time span = 11 days, 22 hours, 33 minutes, 44 seconds
TimeSpan tsX = TimeSpan(11,22,33,44);
// Version = 1.2.333.4
Version^ versX = gcnew Version( "1.2.333.4" );
// Guid = CA761232-ED42-11CE-BACD-00AA0057B223
Guid guidX = Guid( "{CA761232-ED42-11CE-BACD-00AA0057B223}");
Boolean a1 = true,a2 = true;
Byte b1 = 1,b2 = 1;
Int16 c1 = -2,c2 = 2;
Int32 d1 = 3,d2 = 3;
Int64 e1 = 4,e2 = -4;
Decimal f1 = Decimal(-5.5), f2 = Decimal(5.5);
Single g1 = 6.6f,g2 = 6.6f;
Double h1 = 7.7,h2 = -7.7;
Char i1 = 'A',i2 = 'A';
String^ j1 = "abc", ^j2 = "abc";
DateTime k1 = now,k2 = now;
TimeSpan l1 = tsX,l2 = tsX;
Version^ m1 = versX, ^m2 = gcnew Version( "2.0" );
Guid n1 = guidX,n2 = guidX;
// The following types are not CLS-compliant.
SByte w1 = 8,w2 = 8;
UInt16 x1 = 9,x2 = 9;
UInt32 y1 = 10,y2 = 10;
UInt64 z1 = 11,z2 = 11;
//
Console::WriteLine( msg, nl );
try
{
Show( "Boolean: ", a1, a2, a1.CompareTo( a2 ), a1.CompareTo( a2 ) );
Show( "Byte: ", b1, b2, b1.CompareTo( b2 ), b1.CompareTo( b2 ) );
Show( "Int16: ", c1, c2, c1.CompareTo( c2 ), c1.CompareTo( c2 ) );
Show( "Int32: ", d1, d2, d1.CompareTo( d2 ), d1.CompareTo( d2 ) );
Show( "Int64: ", e1, e2, e1.CompareTo( e2 ), e1.CompareTo( e2 ) );
Show( "Decimal: ", f1, f2, f1.CompareTo( f2 ), f1.CompareTo( f2 ) );
Show( "Single: ", g1, g2, g1.CompareTo( g2 ), g1.CompareTo( g2 ) );
Show( "Double: ", h1, h2, h1.CompareTo( h2 ), h1.CompareTo( h2 ) );
Show( "Char: ", i1, i2, i1.CompareTo( i2 ), i1.CompareTo( i2 ) );
// Use an anonymous object to hide the String object.
obj = j2;
Show( "String: ", j1, j2, j1->CompareTo( j2 ), j1->CompareTo( obj ) );
Show( "DateTime:", k1, k2, k1.CompareTo( k2 ), k1.CompareTo( k2 ) );
Show( "TimeSpan: ", l1, l2, l1.CompareTo( l2 ), l1.CompareTo( l2 ) );
// Use an anonymous object to hide the Version object.
obj = m2;
Show( "Version: ", m1, m2, m1->CompareTo( m2 ), m1->CompareTo( obj ) );
Show( "Guid: ", n1, n2, n1.CompareTo( n2 ), n1.CompareTo( n2 ) );
//
Console::WriteLine( "{0}The following types are not CLS-compliant:", nl );
Show( "SByte: ", w1, w2, w1.CompareTo( w2 ), w1.CompareTo( w2 ) );
Show( "UInt16: ", x1, x2, x1.CompareTo( x2 ), x1.CompareTo( x2 ) );
Show( "UInt32: ", y1, y2, y1.CompareTo( y2 ), y1.CompareTo( y2 ) );
Show( "UInt64: ", z1, z2, z1.CompareTo( z2 ), z1.CompareTo( z2 ) );
}
catch ( Exception^ e )
{
Console::WriteLine( e );
}
}
// This example displays the following output:
//
// The following is the result of using the generic and non-generic versions of the
// CompareTo method for several base types:
//
// Boolean: True is equal to True
// Byte: 1 is equal to 1
// Int16: -2 is less than 2
// Int32: 3 is equal to 3
// Int64: 4 is greater than -4
// Decimal: -5.5 is less than 5.5
// Single: 6.6 is equal to 6.6
// Double: 7.7 is greater than -7.7
// Char: A is equal to A
// String: abc is equal to abc
// DateTime: 12/1/2003 5:37:46 PM is equal to 12/1/2003 5:37:46 PM
// TimeSpan: 11.22:33:44 is equal to 11.22:33:44
// Version: 1.2.333.4 is less than 2.0
// Guid: ca761232-ed42-11ce-bacd-00aa0057b223 is equal to ca761232-ed42-11ce-bacd-00
// aa0057b223
//
// The following types are not CLS-compliant:
// SByte: 8 is equal to 8
// UInt16: 9 is equal to 9
// UInt32: 10 is equal to 10
// UInt64: 11 is equal to 11
// This example demonstrates the generic and non-generic versions of the
// CompareTo method for several base types.
// The non-generic version takes a parameter of type Object, while the generic
// version takes a type-specific parameter, such as Boolean, Int32, or Double.
using System;
class Sample
{
public static void Main()
{
string nl = Environment.NewLine;
string msg = "{0}The following is the result of using the generic and non-generic{0}" +
"versions of the CompareTo method for several base types:{0}";
DateTime now = DateTime.Now;
// Time span = 11 days, 22 hours, 33 minutes, 44 seconds
TimeSpan tsX = new TimeSpan(11, 22, 33, 44);
// Version = 1.2.333.4
Version versX = new Version("1.2.333.4");
// Guid = CA761232-ED42-11CE-BACD-00AA0057B223
Guid guidX = new Guid("{CA761232-ED42-11CE-BACD-00AA0057B223}");
Boolean a1 = true, a2 = true;
Byte b1 = 1, b2 = 1;
Int16 c1 = -2, c2 = 2;
Int32 d1 = 3, d2 = 3;
Int64 e1 = 4, e2 = -4;
Decimal f1 = -5.5m, f2 = 5.5m;
Single g1 = 6.6f, g2 = 6.6f;
Double h1 = 7.7d, h2 = -7.7d;
Char i1 = 'A', i2 = 'A';
String j1 = "abc", j2 = "abc";
DateTime k1 = now, k2 = now;
TimeSpan l1 = tsX, l2 = tsX;
Version m1 = versX, m2 = new Version("2.0");
Guid n1 = guidX, n2 = guidX;
// The following types are not CLS-compliant.
SByte w1 = 8, w2 = 8;
UInt16 x1 = 9, x2 = 9;
UInt32 y1 = 10, y2 = 10;
UInt64 z1 = 11, z2 = 11;
//
Console.WriteLine(msg, nl);
try
{
// The second and third Show method call parameters are automatically boxed because
// the second and third Show method declaration arguments expect type Object.
Show("Boolean: ", a1, a2, a1.CompareTo(a2), a1.CompareTo((Object)a2));
Show("Byte: ", b1, b2, b1.CompareTo(b2), b1.CompareTo((Object)b2));
Show("Int16: ", c1, c2, c1.CompareTo(c2), c1.CompareTo((Object)c2));
Show("Int32: ", d1, d2, d1.CompareTo(d2), d1.CompareTo((Object)d2));
Show("Int64: ", e1, e2, e1.CompareTo(e2), e1.CompareTo((Object)e2));
Show("Decimal: ", f1, f2, f1.CompareTo(f2), f1.CompareTo((Object)f2));
Show("Single: ", g1, g2, g1.CompareTo(g2), g1.CompareTo((Object)g2));
Show("Double: ", h1, h2, h1.CompareTo(h2), h1.CompareTo((Object)h2));
Show("Char: ", i1, i2, i1.CompareTo(i2), i1.CompareTo((Object)i2));
Show("String: ", j1, j2, j1.CompareTo(j2), j1.CompareTo((Object)j2));
Show("DateTime: ", k1, k2, k1.CompareTo(k2), k1.CompareTo((Object)k2));
Show("TimeSpan: ", l1, l2, l1.CompareTo(l2), l1.CompareTo((Object)l2));
Show("Version: ", m1, m2, m1.CompareTo(m2), m1.CompareTo((Object)m2));
Show("Guid: ", n1, n2, n1.CompareTo(n2), n1.CompareTo((Object)n2));
//
Console.WriteLine("{0}The following types are not CLS-compliant:", nl);
Show("SByte: ", w1, w2, w1.CompareTo(w2), w1.CompareTo((Object)w2));
Show("UInt16: ", x1, x2, x1.CompareTo(x2), x1.CompareTo((Object)x2));
Show("UInt32: ", y1, y2, y1.CompareTo(y2), y1.CompareTo((Object)y2));
Show("UInt64: ", z1, z2, z1.CompareTo(z2), z1.CompareTo((Object)z2));
}
catch (Exception e)
{
Console.WriteLine(e);
}
}
public static void Show(string caption, Object var1, Object var2,
int resultGeneric, int resultNonGeneric)
{
string relation;
Console.Write(caption);
if (resultGeneric == resultNonGeneric)
{
if (resultGeneric < 0) relation = "less than";
else if (resultGeneric > 0) relation = "greater than";
else relation = "equal to";
Console.WriteLine("{0} is {1} {2}", var1, relation, var2);
}
// The following condition will never occur because the generic and non-generic
// CompareTo methods are equivalent.
else
{
Console.WriteLine("Generic CompareTo = {0}; non-generic CompareTo = {1}",
resultGeneric, resultNonGeneric);
}
}
}
/*
This example produces the following results:
The following is the result of using the generic and non-generic versions of the
CompareTo method for several base types:
Boolean: True is equal to True
Byte: 1 is equal to 1
Int16: -2 is less than 2
Int32: 3 is equal to 3
Int64: 4 is greater than -4
Decimal: -5.5 is less than 5.5
Single: 6.6 is equal to 6.6
Double: 7.7 is greater than -7.7
Char: A is equal to A
String: abc is equal to abc
DateTime: 12/1/2003 5:37:46 PM is equal to 12/1/2003 5:37:46 PM
TimeSpan: 11.22:33:44 is equal to 11.22:33:44
Version: 1.2.333.4 is less than 2.0
Guid: ca761232-ed42-11ce-bacd-00aa0057b223 is equal to ca761232-ed42-11ce-bacd-00
aa0057b223
The following types are not CLS-compliant:
SByte: 8 is equal to 8
UInt16: 9 is equal to 9
UInt32: 10 is equal to 10
UInt64: 11 is equal to 11
*/
// This example demonstrates the generic and non-generic versions of the
// CompareTo method for several base types.
// The non-generic version takes a parameter of type Object, while the generic
// version takes a type-specific parameter, such as Boolean, Int32, or Double.
open System
let show caption (var1: obj) (var2: obj) resultGeneric resultNonGeneric =
printf "%s" caption
if resultGeneric = resultNonGeneric then
let relation =
if resultGeneric < 0 then "less than"
elif resultGeneric > 0 then "greater than"
else "equal to"
printfn $"{var1} is {relation} {var2}"
// The following condition will never occur because the generic and non-generic
// CompareTo methods are equivalent.
else
printfn $"Generic CompareTo = {resultGeneric} non-generic CompareTo = {resultNonGeneric}"
let now = DateTime.Now
// Time span = 11 days, 22 hours, 33 minutes, 44 seconds
let tsX = TimeSpan(11, 22, 33, 44)
// Version = 1.2.333.4
let versX = Version "1.2.333.4"
// Guid = CA761232-ED42-11CE-BACD-00AA0057B223
let guidX = Guid "{CA761232-ED42-11CE-BACD-00AA0057B223}"
let a1, a2 = true, true
let b1, b2 = 1uy, 1uy
let c1, c2 = -2s, 2s
let d1, d2 = 3, 3
let e1, e2 = 4L, -4L
let f1, f2 = -5.5m, 5.5m
let g1, g2 = 6.6f, 6.6f
let h1, h2 = 7.7, -7.7
let i1, i2 = 'A', 'A'
let j1, j2 = "abc", "abc"
let k1, k2 = now, now
let l1, l2 = tsX, tsX
let m1, m2 = versX, Version "2.0"
let n1, n2 = guidX, guidX
// The following types are not CLS-compliant.
let w1, w2 = 8y, 8y
let x1, x2 = 9us, 9us
let y1, y2 = 10u, 10u
let z1, z2 = 11uL, 11uL
printfn "\nThe following is the result of using the generic and non-generic\nversions of the CompareTo method for several base types:\n"
try
// The second and third show function call parameters are automatically boxed because
// the second and third show function declaration arguments expect type Object.
show "Boolean: " a1 a2 (a1.CompareTo a2) (a1.CompareTo (a2 :> obj))
show "Byte: " b1 b2 (b1.CompareTo b2) (b1.CompareTo (b2 :> obj))
show "Int16: " c1 c2 (c1.CompareTo c2) (c1.CompareTo (c2 :> obj))
show "Int32: " d1 d2 (d1.CompareTo d2) (d1.CompareTo (d2 :> obj))
show "Int64: " e1 e2 (e1.CompareTo e2) (e1.CompareTo (e2 :> obj))
show "Decimal: " f1 f2 (f1.CompareTo f2) (f1.CompareTo (f2 :> obj))
show "Single: " g1 g2 (g1.CompareTo g2) (g1.CompareTo (g2 :> obj))
show "Double: " h1 h2 (h1.CompareTo h2) (h1.CompareTo (h2 :> obj))
show "Char: " i1 i2 (i1.CompareTo i2) (i1.CompareTo (i2 :> obj))
show "String: " j1 j2 (j1.CompareTo j2) (j1.CompareTo (j2 :> obj))
show "DateTime: " k1 k2 (k1.CompareTo k2) (k1.CompareTo (k2 :> obj))
show "TimeSpan: " l1 l2 (l1.CompareTo l2) (l1.CompareTo (l2 :> obj))
show "Version: " m1 m2 (m1.CompareTo m2) (m1.CompareTo (m2 :> obj))
show "Guid: " n1 n2 (n1.CompareTo n2) (n1.CompareTo (n2 :> obj))
printfn "\nThe following types are not CLS-compliant:"
show "SByte: " w1 w2 (w1.CompareTo w2) (w1.CompareTo (w2 :> obj))
show "UInt16: " x1 x2 (x1.CompareTo x2) (x1.CompareTo (x2 :> obj))
show "UInt32: " y1 y2 (y1.CompareTo y2) (y1.CompareTo (y2 :> obj))
show "UInt64: " z1 z2 (z1.CompareTo z2) (z1.CompareTo (z2 :> obj))
with e -> printfn $"{e}"
// This example produces the following results:
// The following is the result of using the generic and non-generic versions of the
// CompareTo method for several base types:
// Boolean: True is equal to True
// Byte: 1 is equal to 1
// Int16: -2 is less than 2
// Int32: 3 is equal to 3
// Int64: 4 is greater than -4
// Decimal: -5.5 is less than 5.5
// Single: 6.6 is equal to 6.6
// Double: 7.7 is greater than -7.7
// Char: A is equal to A
// String: abc is equal to abc
// DateTime: 12/1/2003 5:37:46 PM is equal to 12/1/2003 5:37:46 PM
// TimeSpan: 11.22:33:44 is equal to 11.22:33:44
// Version: 1.2.333.4 is less than 2.0
// Guid: ca761232-ed42-11ce-bacd-00aa0057b223 is equal to ca761232-ed42-11ce-bacd-00
// aa0057b223
// The following types are not CLS-compliant:
// SByte: 8 is equal to 8
// UInt16: 9 is equal to 9
// UInt32: 10 is equal to 10
// UInt64: 11 is equal to 11
' This example demonstrates the generic and non-generic versions of the
' CompareTo method for several base types.
' The non-generic version takes a parameter of type Object, while the generic
' version takes a type-specific parameter, such as Boolean, Int32, or Double.
Class Sample
Public Shared Sub Main()
Dim nl As String = Environment.NewLine
Dim msg As String = _
"{0}The following is the result of using the generic and non-generic{0}" & _
"versions of the CompareTo method for several base types:{0}"
Dim now As DateTime = DateTime.Now
' Time span = 11 days, 22 hours, 33 minutes, 44 seconds
Dim tsX As New TimeSpan(11, 22, 33, 44)
' Version = 1.2.333.4
Dim versX As New Version("1.2.333.4")
' Guid = CA761232-ED42-11CE-BACD-00AA0057B223
Dim guidX As New Guid("{CA761232-ED42-11CE-BACD-00AA0057B223}")
Dim a1 As [Boolean] = True, a2 As [Boolean] = True
Dim b1 As [Byte] = 1, b2 As [Byte] = 1
Dim c1 As Int16 = -2, c2 As Int16 = 2
Dim d1 As Int32 = 3, d2 As Int32 = 3
Dim e1 As Int64 = 4, e2 As Int64 = -4
Dim f1 As [Decimal] = -5.5D, f2 As [Decimal] = 5.5D
Dim g1 As [Single] = 6.6F, g2 As [Single] = 6.6F
Dim h1 As [Double] = 7.7, h2 As [Double] = -7.7
Dim i1 As [Char] = "A"c, i2 As [Char] = "A"c
Dim j1 As String = "abc", j2 As String = "abc"
Dim k1 As DateTime = now, k2 As DateTime = now
Dim l1 As TimeSpan = tsX, l2 As TimeSpan = tsX
Dim m1 As Version = versX, m2 As New Version("2.0")
Dim n1 As Guid = guidX, n2 As Guid = guidX
' The following types are not CLS-compliant.
' SByte, UInt16, UInt32, UInt64
Console.WriteLine(msg, nl)
Try
' The second and third Show method call parameters are automatically boxed because
' the second and third Show method declaration arguments expect type Object.
Show("Boolean: ", a1, a2, a1.CompareTo(a2), a1.CompareTo(CObj(a2)))
Show("Byte: ", b1, b2, b1.CompareTo(b2), b1.CompareTo(CObj(b2)))
Show("Int16: ", c1, c2, c1.CompareTo(c2), c1.CompareTo(CObj(c2)))
Show("Int32: ", d1, d2, d1.CompareTo(d2), d1.CompareTo(CObj(d2)))
Show("Int64: ", e1, e2, e1.CompareTo(e2), e1.CompareTo(CObj(e2)))
Show("Decimal: ", f1, f2, f1.CompareTo(f2), f1.CompareTo(CObj(f2)))
Show("Single: ", g1, g2, g1.CompareTo(g2), g1.CompareTo(CObj(g2)))
Show("Double: ", h1, h2, h1.CompareTo(h2), h1.CompareTo(CObj(h2)))
Show("Char: ", i1, i2, i1.CompareTo(i2), i1.CompareTo(CObj(i2)))
Show("String: ", j1, j2, j1.CompareTo(j2), j1.CompareTo(CObj(j2)))
Show("DateTime: ", k1, k2, k1.CompareTo(k2), k1.CompareTo(CObj(k2)))
Show("TimeSpan: ", l1, l2, l1.CompareTo(l2), l1.CompareTo(CObj(l2)))
Show("Version: ", m1, m2, m1.CompareTo(m2), m1.CompareTo(CObj(m2)))
Show("Guid: ", n1, n2, n1.CompareTo(n2), n1.CompareTo(CObj(n2)))
'
Console.WriteLine("{0}The following types are not CLS-compliant:", nl)
Console.WriteLine("SByte, UInt16, UInt32, UInt64")
Catch e As Exception
Console.WriteLine(e)
End Try
End Sub
Public Shared Sub Show(caption As String, var1 As [Object], var2 As [Object], _
resultGeneric As Integer, resultNonGeneric As Integer)
Dim relation As String
Console.Write(caption)
If resultGeneric = resultNonGeneric Then
If resultGeneric < 0 Then
relation = "less than"
ElseIf resultGeneric > 0 Then
relation = "greater than"
Else
relation = "equal to"
End If
Console.WriteLine("{0} is {1} {2}", var1, relation, var2)
' The following condition will never occur because the generic and non-generic
' CompareTo methods are equivalent.
Else
Console.WriteLine("Generic CompareTo = {0}; non-generic CompareTo = {1}", _
resultGeneric, resultNonGeneric)
End If
End Sub
End Class
'
'This example produces the following results:
'
'The following is the result of using the generic and non-generic versions of the
'CompareTo method for several base types:
'
'Boolean: True is equal to True
'Byte: 1 is equal to 1
'Int16: -2 is less than 2
'Int32: 3 is equal to 3
'Int64: 4 is greater than -4
'Decimal: -5.5 is less than 5.5
'Single: 6.6 is equal to 6.6
'Double: 7.7 is greater than -7.7
'Char: A is equal to A
'String: abc is equal to abc
'DateTime: 12/1/2003 5:37:46 PM is equal to 12/1/2003 5:37:46 PM
'TimeSpan: 11.22:33:44 is equal to 11.22:33:44
'Version: 1.2.333.4 is less than 2.0
'Guid: ca761232-ed42-11ce-bacd-00aa0057b223 is equal to ca761232-ed42-11ce-bacd-00
'aa0057b223
'
'The following types are not CLS-compliant:
'SByte, UInt16, UInt32, UInt64
'
Remarks
This method performs a word (case-sensitive and culture-sensitive) comparison using the current culture. For more information about word, string, and ordinal sorts, see System.Globalization.CompareOptions.
Caution
The CompareTo method was designed primarily for use in sorting or alphabetizing operations. It should not be used when the primary purpose of the method call is to determine whether two strings are equivalent. To determine whether two strings are equivalent, call the Equals method.
For more information about the behavior of this method, see the Remarks section of the Compare(String, String) method.
This method implements the System.IComparable<T> interface and performs slightly better than the String.CompareTo(Object) method, because it does not have to determine whether the strB
argument is a mutable value type that must be boxed, and it does not have to cast its parameter from an Object to a String.
Notes to Callers
Character sets include ignorable characters. The CompareTo(String) method does not consider such characters when it performs a culture-sensitive comparison. For example, if the following code is run on the .NET Framework 4 or later, a comparison of "animal" with "ani-mal" (using a soft hyphen, or U+00AD) indicates that the two strings are equivalent.
using System;
public class Example
{
public static void Main()
{
string s1 = "ani\u00ADmal";
string s2 = "animal";
Console.WriteLine("Comparison of '{0}' and '{1}': {2}",
s1, s2, s1.CompareTo(s2));
}
}
// The example displays the following output:
// Comparison of 'ani-mal' and 'animal': 0
let s1 = "ani\u00ADmal"
let s2 = "animal"
printfn $"Comparison of '{s1}' and '{s2}': {s1.CompareTo s2}"
// The example displays the following output:
// Comparison of 'ani-mal' and 'animal': 0
Module Example
Public Sub Main()
Dim s1 As String = "ani" + ChrW(&h00AD) + "mal"
Dim s2 As String = "animal"
Console.WriteLine("Comparison of '{0}' and '{1}': {2}",
s1, s2, s1.CompareTo(s2))
End Sub
End Module
' The example displays the following output:
' Comparison of 'ani-mal' and 'animal': 0
To recognize ignorable characters in a string comparison, call the CompareOrdinal(String, String) method.
See also
Applies to
.NET 9 and other versions
Product | Versions |
---|---|
.NET | Core 1.0, Core 1.1, Core 2.0, Core 2.1, Core 2.2, Core 3.0, Core 3.1, 5, 6, 7, 8, 9 |
.NET Framework | 1.1, 2.0, 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1 |
.NET Standard | 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 2.0, 2.1 |
UWP | 10.0 |
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