Char.CompareTo Metoda
Definice
Důležité
Některé informace platí pro předběžně vydaný produkt, který se může zásadně změnit, než ho výrobce nebo autor vydá. Microsoft neposkytuje žádné záruky, výslovné ani předpokládané, týkající se zde uváděných informací.
Porovná tuto instanci se zadaným objektem nebo typem hodnoty a určuje, jestli tato instance předchází, následuje nebo se objevuje na stejné pozici v pořadí řazení jako zadaný objekt nebo typ hodnoty.
Přetížení
| CompareTo(Char) |
Porovná tuto instanci se zadaným objektem a určuje, jestli tato instance předchází, následuje nebo se objevuje na stejné pozici v pořadí řazení Char jako zadaný Char objekt. |
| CompareTo(Object) |
Porovná tuto instanci se zadaným objektem a určí, zda tato instance předchází, následuje nebo se zobrazí ve stejné pozici v pořadí řazení jako zadané Object . |
CompareTo(Char)
public:
virtual int CompareTo(char value);public int CompareTo (char value);abstract member CompareTo : char -> int
override this.CompareTo : char -> intPublic Function CompareTo (value As Char) As IntegerParametry
Návraty
Číslo se znaménkem označující pozici této instance v pořadí řazení ve vztahu k value parametru .
| Návratová hodnota | Popis |
|---|---|
| Menší než nula | Tato instance předchází value .
|
| Žádnou | Tato instance má stejnou pozici v pořadí řazení jako value .
|
| Větší než nula | Tato instance následuje value za .
|
Implementuje
Příklady
Následující příklad kódu ukazuje obecné a neobecné verze CompareTo metody pro několik typů hodnot a odkazů.
// 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.
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
'
Poznámky
Tato metoda implementuje rozhraní a provádí trochu lepší výkon než metoda , protože nemusí převést System.IComparable<T> Char.CompareTo parametr na value objekt.
Porovnání prováděné touto metodou je založené na kódovaných hodnotách této instance a value , nikoli na jejich lexikografických vlastnostech.
Pokud má typ parametru metody méně bitů (je užší) než typ instance, některé programovací jazyky provádějí implicitní rozšiřující převod, který transformuje hodnotu parametru na hodnotu s více CompareTo bity.
Předpokládejme například, že typ instance je a Int32 typ parametru je Byte . Kompilátor jazyka Microsoft C# generuje instrukce, které představují hodnotu parametru jako objekt, a poté vygeneruje metodu, která porovnává hodnoty Int32 instance a Int32.CompareTo Int32 reprezentaci Int32 parametru.
Implicitní rozšiřující převody se obvykle provádějí u číselných typů. V dokumentaci k programovacímu jazyku zjistěte, jestli jeho kompilátor provádí rozšiřující převody. Pokud instance a typy parametrů neodpovídají a vhodný převod není k dispozici, kompilátor vygeneruje instrukce pro pole parametru a vyvolání přetížení, CompareTo které přijímá Object parametr .
Viz také
Platí pro
CompareTo(Object)
Porovná tuto instanci se zadaným objektem a určí, zda tato instance předchází, následuje nebo se zobrazí ve stejné pozici v pořadí řazení jako zadané Object .
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 -> intPublic Function CompareTo (value As Object) As IntegerParametry
- value
- Object
Objekt, na který se má porovnat tato instance, nebo null .
Návraty
Číslo se znaménkem označující pozici této instance v pořadí řazení ve vztahu k value parametru.
| Návratová hodnota | Popis |
|---|---|
| Menší než nula | Tato instance předchází value .
|
| Žádnou | Tato instance má stejné umístění v pořadí řazení jako value .
|
| Větší než nula | Tato instance následuje po value .
-nebo-
|
Implementuje
Výjimky
value není Char objekt.
Příklady
Následující příklad kódu ukazuje CompareTo .
using namespace System;
int main()
{
char chA = 'A';
char chB = 'B';
Console::WriteLine( chA.CompareTo( 'A' ) ); // Output: "0" (meaning they're equal)
Console::WriteLine( 'b'.CompareTo( chB ) ); // Output: "32" (meaning 'b' is greater than 'B' by 32)
Console::WriteLine( chA.CompareTo( chB ) ); // Output: "-1" (meaning 'A' is less than 'B' by 1)
}
using System;
public class CompareToSample {
public static void Main() {
char chA = 'A';
char chB = 'B';
Console.WriteLine(chA.CompareTo('A')); // Output: "0" (meaning they're equal)
Console.WriteLine('b'.CompareTo(chB)); // Output: "32" (meaning 'b' is greater than 'B' by 32)
Console.WriteLine(chA.CompareTo(chB)); // Output: "-1" (meaning 'A' is less than 'B' by 1)
}
}
let chA = 'A'
let chB = 'B'
printfn $"{chA.CompareTo 'A'}" // Output: "0" (meaning they're equal)
printfn $"{'b'.CompareTo chB}" // Output: "32" (meaning 'b' is greater than 'B' by 32)
printfn $"{chA.CompareTo chB}" // Output: "-1" (meaning 'A' is less than 'B' by 1)
Module CompareToSample
Sub Main()
Dim chA As Char
chA = "A"c
Dim chB As Char
chB = "B"c
Console.WriteLine(chA.CompareTo("A"c)) ' Output: "0" (meaning they're equal)
Console.WriteLine("b"c.CompareTo(chB)) ' Output: "32" (meaning 'b' is 32 greater than 'B')
Console.WriteLine(chA.CompareTo(chB)) ' Output: "-1" (meaning 'A' is less than 'B' by 1)
End Sub
End Module
Poznámky
CompareToMetoda implementuje IComparable rozhraní.
valueParametr musí být null nebo instance Char ; v opačném případě je vyvolána výjimka.
Porovnání provedené touto metodou je založeno na kódovaných hodnotách této instance value , a ne nutně jejich lexicographical charakteristiky. Jakékoli instance Char , bez ohledu na její hodnotu, se považují za větší než null .