Type.MakeByRefType 方法
定义
重要
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返回一个 Type 对象,该对象表示在作为 ref 参数(Visual Basic 中的ByRef 参数)传递时当前类型。
public:
abstract Type ^ MakeByRefType();
public:
virtual Type ^ MakeByRefType();
public abstract Type MakeByRefType();
public virtual Type MakeByRefType();
abstract member MakeByRefType : unit -> Type
abstract member MakeByRefType : unit -> Type
override this.MakeByRefType : unit -> Type
Public MustOverride Function MakeByRefType () As Type
Public Overridable Function MakeByRefType () As Type
返回
Type 对象,表示作为 ref 参数(Visual Basic中的 ByRef 参数)传递时当前类型。
例外
基类不支持调用的方法。
示例
下面的代码示例为 ref 类创建数组、ByRef(Test Visual Basic)和指针类型。
using System;
using System.Reflection;
public class Example
{
public static void Main()
{
// Create a Type object that represents a one-dimensional
// array of Example objects.
Type t = typeof(Example).MakeArrayType();
Console.WriteLine("\r\nArray of Example: {0}", t);
// Create a Type object that represents a two-dimensional
// array of Example objects.
t = typeof(Example).MakeArrayType(2);
Console.WriteLine("\r\nTwo-dimensional array of Example: {0}", t);
// Demonstrate an exception when an invalid array rank is
// specified.
try
{
t = typeof(Example).MakeArrayType(-1);
}
catch(Exception ex)
{
Console.WriteLine("\r\n{0}", ex);
}
// Create a Type object that represents a ByRef parameter
// of type Example.
t = typeof(Example).MakeByRefType();
Console.WriteLine("\r\nByRef Example: {0}", t);
// Get a Type object representing the Example class, a
// MethodInfo representing the "Test" method, a ParameterInfo
// representing the parameter of type Example, and finally
// a Type object representing the type of this ByRef parameter.
// Compare this Type object with the Type object created using
// MakeByRefType.
Type t2 = typeof(Example);
MethodInfo mi = t2.GetMethod("Test");
ParameterInfo pi = mi.GetParameters()[0];
Type pt = pi.ParameterType;
Console.WriteLine("Are the ByRef types equal? {0}", (t == pt));
// Create a Type object that represents a pointer to an
// Example object.
t = typeof(Example).MakePointerType();
Console.WriteLine("\r\nPointer to Example: {0}", t);
}
// A sample method with a ByRef parameter.
//
public void Test(ref Example e)
{
}
}
/* This example produces output similar to the following:
Array of Example: Example[]
Two-dimensional array of Example: Example[,]
System.IndexOutOfRangeException: Index was outside the bounds of the array.
at System.RuntimeType.MakeArrayType(Int32 rank) in c:\vbl\ndp\clr\src\BCL\System\RtType.cs:line 2999
at Example.Main()
ByRef Example: Example&
Are the ByRef types equal? True
Pointer to Example: Example*
*/
type Example() =
// A sample method with a ByRef parameter.
member _.Test(e: Example byref) = ()
do
// Create a Type object that represents a one-dimensional
// array of Example objects.
let t = typeof<Example>.MakeArrayType()
printfn $"\r\nArray of Example: {t}"
// Create a Type object that represents a two-dimensional
// array of Example objects.
let t = typeof<Example>.MakeArrayType 2
printfn $"\r\nTwo-dimensional array of Example: {t}"
// Demonstrate an exception when an invalid array rank is
// specified.
try
let t = typeof<Example>.MakeArrayType -1
()
with ex ->
printfn $"\r\n{ex}"
// Create a Type object that represents a ByRef parameter
// of type Example.
let t = typeof<Example>.MakeByRefType()
printfn $"\r\nByRef Example: {t}"
// Get a Type object representing the Example class, a
// MethodInfo representing the "Test" method, a ParameterInfo
// representing the parameter of type Example, and finally
// a Type object representing the type of this ByRef parameter.
// Compare this Type object with the Type object created using
// MakeByRefType.
let t2 = typeof<Example>
let mi = t2.GetMethod "Test"
let pi = mi.GetParameters()[0]
let pt = pi.ParameterType
printfn $"Are the ByRef types equal? {t = pt}"
// Create a Type object that represents a pointer to an
// Example object.
let t = typeof<Example>.MakePointerType()
printfn $"\r\nPointer to Example: {t}"
(* This example produces output similar to the following:
Array of Example: Example[]
Two-dimensional array of Example: Example[,]
System.IndexOutOfRangeException: Index was outside the bounds of the array.
at System.RuntimeType.MakeArrayType(Int32 rank) in c:\vbl\ndp\clr\src\BCL\System\RtType.cs:line 2999
at Example.Main()
ByRef Example: Example&
Are the ByRef types equal? True
Pointer to Example: Example*
*)
Imports System.Reflection
Public Class Example
Public Shared Sub Main()
' Create a Type object that represents a one-dimensional
' array of Example objects.
Dim t As Type = GetType(Example).MakeArrayType()
Console.WriteLine(vbCrLf & "Array of Example: " & t.ToString())
' Create a Type object that represents a two-dimensional
' array of Example objects.
t = GetType(Example).MakeArrayType(2)
Console.WriteLine(vbCrLf & "Two-dimensional array of Example: " & t.ToString())
' Demonstrate an exception when an invalid array rank is
' specified.
Try
t = GetType(Example).MakeArrayType(-1)
Catch ex As Exception
Console.WriteLine(vbCrLf & ex.ToString())
End Try
' Create a Type object that represents a ByRef parameter
' of type Example.
t = GetType(Example).MakeByRefType()
Console.WriteLine(vbCrLf & "ByRef Example: " & t.ToString())
' Get a Type object representing the Example class, a
' MethodInfo representing the "Test" method, a ParameterInfo
' representing the parameter of type Example, and finally
' a Type object representing the type of this ByRef parameter.
' Compare this Type object with the Type object created using
' MakeByRefType.
Dim t2 As Type = GetType(Example)
Dim mi As MethodInfo = t2.GetMethod("Test")
Dim pi As ParameterInfo = mi.GetParameters()(0)
Dim pt As Type = pi.ParameterType
Console.WriteLine("Are the ByRef types equal? " & (t Is pt))
' Create a Type object that represents a pointer to an
' Example object.
t = GetType(Example).MakePointerType()
Console.WriteLine(vbCrLf & "Pointer to Example: " & t.ToString())
End Sub
' A sample method with a ByRef parameter.
'
Public Sub Test(ByRef e As Example)
End Sub
End Class
' This example produces output similar to the following:
'
'Array of Example: Example[]
'
'Two-dimensional array of Example: Example[,]
'
'System.IndexOutOfRangeException: Index was outside the bounds of the array.
' at System.RuntimeType.MakeArrayType(Int32 rank) in c:\vbl\ndp\clr\src\BCL\System\RtType.cs:line 2999
' at Example.Main()
'
'ByRef Example: Example&
'Are the ByRef types equal? True
'
'Pointer to Example: Example*
注解
MakeByRefType 方法提供了为参数列表生成 ref 类型(Visual Basic ByRef)的方法。
如果使用Microsoft中间语言(MSIL)的语法,如果当前 Type 对象表示 Int32,此方法将返回表示 Type 的 Int32& 对象。