Type.Equals Method
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Equals(Type) |
Determines if the underlying system type of the current Type is the same as the underlying system type of the specified Type. |
Equals(Object) |
Determines if the underlying system type of the current Type object is the same as the underlying system type of the specified Object. |
- Source:
- Type.cs
- Source:
- Type.cs
- Source:
- Type.cs
public:
bool Equals(Type ^ o);
public:
virtual bool Equals(Type ^ o);
public bool Equals (Type o);
public virtual bool Equals (Type? o);
public virtual bool Equals (Type o);
override this.Equals : Type -> bool
Public Function Equals (o As Type) As Boolean
Public Overridable Function Equals (o As Type) As Boolean
Parameters
- o
- Type
The object whose underlying system type is to be compared with the underlying system type of the current Type.
Returns
true
if the underlying system type of o
is the same as the underlying system type of the current Type; otherwise, false
.
Implements
Examples
The following example uses Equals
to compare two types.
using System;
using System.Reflection;
class Example
{
public static void Main()
{
Type a = typeof(System.String);
Type b = typeof(System.Int32);
Console.WriteLine("{0} == {1}: {2}", a, b, a.Equals(b));
// The Type objects in a and b are not equal,
// because they represent different types.
a = typeof(Example);
b = new Example().GetType();
Console.WriteLine("{0} is equal to {1}: {2}", a, b, a.Equals(b));
// The Type objects in a and b are equal,
// because they both represent type Example.
b = typeof(Type);
Console.WriteLine("typeof({0}).Equals(typeof({1})): {2}", a, b, a.Equals(b));
// The Type objects in a and b are not equal,
// because variable a represents type Example
// and variable b represents type Type.
//Console.ReadLine();
}
}
//
/* This code example produces the following output:
System.String == System.Int32: False
Example is equal to Example: True
typeof(Example).Equals(typeof(System.Type)): False
*/
open System
type Example() = class end
do
let a = typeof<string>
let b = typeof<int>
printfn $"{a} == {b}: {a.Equals b}"
// The Type objects in a and b are not equal,
// because they represent different types.
let a = typeof<Example>
let b = Example().GetType()
printfn $"{a} is equal to {b}: {a.Equals b}"
// The Type objects in a and b are equal,
// because they both represent type Example.
let b = typeof<Type>
printfn $"typeof({a}).Equals(typeof({b})): {a.Equals b}"
// The Type objects in a and b are not equal,
// because variable a represents type Example
// and variable b represents type Type.
(* This code example produces the following output:
System.String == System.Int32: False
Example is equal to Example: True
typeof(Example).Equals(typeof(System.Type)): False
*)
Imports System.Reflection
Class Example
Public Shared Sub Main()
Dim a As Type = GetType(System.String)
Dim b As Type = GetType(System.Int32)
Console.WriteLine("{0} = {1}: {2}", a, b, a.Equals(b))
' The Type objects in a and b are not equal,
' because they represent different types.
a = GetType(Example)
b = New Example().GetType()
Console.WriteLine("{0} is equal to {1}: {2}", a, b, a.Equals(b))
' The Type objects in a and b are equal,
' because they both represent type Example.
b = GetType(Type)
Console.WriteLine("typeof({0}).Equals(typeof({1})): {2}", a, b, a.Equals(b))
' The Type objects in a and b are not equal,
' because variable a represents type Example
' and variable b represents type Type.
'Console.ReadLine()
End Sub
End Class
'
' This code example produces the following output:
' System.String = System.Int32: False
' Example is equal to Example: True
' typeof(Example).Equals(typeof(System.Type)): False
'
See also
Applies to
.NET 9 и другие версии
Продукт | Версии |
---|---|
.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 |
- Source:
- Type.cs
- Source:
- Type.cs
- Source:
- Type.cs
public:
override bool Equals(System::Object ^ o);
public override bool Equals (object o);
public override bool Equals (object? o);
override this.Equals : obj -> bool
Public Overrides Function Equals (o As Object) As Boolean
Parameters
- o
- Object
The object whose underlying system type is to be compared with the underlying system type of the current Type. For the comparison to succeed, o
must be able to be cast or converted to an object of type Type.
Returns
true
if the underlying system type of o
is the same as the underlying system type of the current Type; otherwise, false
. This method also returns false
if:
o
isnull
.o
cannot be cast or converted to a Type object.
Implements
Examples
The following example uses Equals(Object) to compare various Type object instances with various Object instances.
using System;
using System.Collections.Generic;
using System.Reflection;
public class Example
{
public static void Main()
{
Type t =typeof(int);
Object obj1 = typeof(int).GetTypeInfo();
IsEqualTo(t, obj1);
Object obj2 = typeof(String);
IsEqualTo(t, obj2);
t = typeof(Object);
Object obj3 = typeof(Object);
IsEqualTo(t, obj3);
t = typeof(List<>);
Object obj4 = (new List<String>()).GetType();
IsEqualTo(t, obj4);
t = typeof(Type);
Object obj5 = null;
IsEqualTo(t, obj5);
}
private static void IsEqualTo(Type t, Object inst)
{
Type t2 = inst as Type;
if (t2 != null)
Console.WriteLine("{0} = {1}: {2}", t.Name, t2.Name,
t.Equals(t2));
else
Console.WriteLine("Cannot cast the argument to a type.");
Console.WriteLine();
}
}
// The example displays the following output:
// Int32 = Int32: True
//
// Int32 = String: False
//
// Object = Object: True
//
// List`1 = List`1: False
//
// Cannot cast the argument to a type.
open System
open System.Reflection
let isEqualTo (t: Type) (inst: obj) =
match inst with
| :? Type as t2 ->
printfn $"{t.Name} = {t2.Name}: {t.Equals t2}\n"
| _ ->
printfn "Cannot cast the argument to a type.\n"
do
let t = typeof<int>
typeof<int>.GetTypeInfo()
|> isEqualTo t
typeof<String>
|> isEqualTo t
let t = typeof<obj>
typeof<obj>
|> isEqualTo t
let t = typeof<ResizeArray<_>>.GetGenericTypeDefinition()
let obj4: obj = (ResizeArray<String>()).GetType()
isEqualTo t obj4
let t = typeof<Type>
let obj5: obj = null
isEqualTo t obj5
// The example displays the following output:
// Int32 = Int32: True
//
// Int32 = String: False
//
// Object = Object: True
//
// List`1 = List`1: False
//
// Cannot cast the argument to a type.
Imports System.Collections.Generic
Imports System.Reflection
Module Example
Public Sub Main()
Dim t As Type = GetType(Integer)
Dim obj1 As Object = GetType(Integer).GetTypeInfo()
IsEqualTo(t, obj1)
Dim obj2 As Object = GetType(String)
IsEqualTo(t, obj2)
t = GetType(Object)
Dim obj3 As Object = GetType(Object)
IsEqualTo(t, obj3)
t = GetType(List(Of ))
Dim obj4 As Object = (New List(Of String())).GetType()
IsEqualTo(t, obj4)
t = GetType(Type)
Dim obj5 As Object = Nothing
IsEqualTo(t, obj5)
End Sub
Private Sub IsEqualTo(t As Type, inst As Object)
Dim t2 As Type = TryCast(inst, Type)
If t2 IsNot Nothing Then
Console.WriteLine("{0} = {1}: {2}", t.Name, t2.Name,
t.Equals(t2))
Else
Console.WriteLine("Cannot cast the argument to a type.")
End If
Console.WriteLine()
End Sub
End Module
' The example displays the following output:
' Int32 = Int32: True
'
' Int32 = String: False
'
' Object = Object: True
'
' List`1 = List`1: False
'
' Cannot cast the argument to a type.
Two things are particularly worth noting about the example:
The comparison of a Type object that represents an integer with a TypeInfo object that represents an integer return
true
because TypeInfo is derived from Type.The comparison of a Type object that represents a IList<T> object (an open generic type) with a
List(Of String)
object (a closed generic type) returnsfalse
.
Remarks
This method overrides Object.Equals. It casts o
to an object of type Type and calls the Type.Equals(Type) method.
See also
Applies to
.NET 9 и другие версии
Продукт | Версии |
---|---|
.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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