Type.HasElementType Propriedade

public:
 property bool HasElementType { bool get(); };

public bool HasElementType { get; }

member this.HasElementType : bool

Public ReadOnly Property HasElementType As Boolean

Valor de Propriedade

true se o Type for um array, um ponteiro, ou for passado por referência; caso contrário, false.

Implementações

Exemplos

O exemplo seguinte retorna true ou false dependendo se o objeto é um array, um tipo de referência ou um apontador.

// This code must be compiled with the /unsafe switch:
//   csc /unsafe source.cs
using System;
using System.Reflection;

public class Example
{
    // This method is for demonstration purposes.
    unsafe public void Test(ref int x, out int y, int* z)
    {
        *z = x = y = 0;
    }

    public static void Main()
    {
        // All of the following display 'True'.

        // Define an array, get its type, and display HasElementType.
        int[] nums = {1, 1, 2, 3, 5, 8, 13};
        Type t = nums.GetType();
        Console.WriteLine("HasElementType is '{0}' for array types.", t.HasElementType);

        // Test an array type without defining an array.
        t = typeof(Example[]);
        Console.WriteLine("HasElementType is '{0}' for array types.", t.HasElementType);

        // When you use Reflection Emit to emit dynamic methods and
        // assemblies, you can create array types using MakeArrayType.
        // The following creates the type 'array of Example'.
        t = typeof(Example).MakeArrayType();
        Console.WriteLine("HasElementType is '{0}' for array types.", t.HasElementType);

        // When you reflect over methods, HasElementType is true for
        // ref, out, and pointer parameter types. The following
        // gets the Test method, defined above, and examines its
        // parameters.
        MethodInfo mi = typeof(Example).GetMethod("Test");
        ParameterInfo[] parms = mi.GetParameters();
        t = parms[0].ParameterType;
        Console.WriteLine("HasElementType is '{0}' for ref parameter types.", t.HasElementType);
        t = parms[1].ParameterType;
        Console.WriteLine("HasElementType is '{0}' for out parameter types.", t.HasElementType);
        t = parms[2].ParameterType;
        Console.WriteLine("HasElementType is '{0}' for pointer parameter types.", t.HasElementType);

        // When you use Reflection Emit to emit dynamic methods and
        // assemblies, you can create pointer and ByRef types to use
        // when you define method parameters.
        t = typeof(Example).MakePointerType();
        Console.WriteLine("HasElementType is '{0}' for pointer types.", t.HasElementType);
        t = typeof(Example).MakeByRefType();
        Console.WriteLine("HasElementType is '{0}' for ByRef types.", t.HasElementType);
    }
}

#nowarn "9"
open FSharp.NativeInterop

type Example() =
    // This method is for demonstration purposes.
    member _.Test(x: int byref, y: int outref, z: int nativeptr) =
        x <- 0
        y <- 0
        NativePtr.write z 0

// All of the following display 'True'.

do
    // Define an array, get its type, and display HasElementType.
    let nums = [| 1; 1; 2; 3; 5; 8; 13 |]
    let t = nums.GetType()
    printfn $"HasElementType is '{t.HasElementType}' for array types."

    // Test an array type without defining an array.
    let t = typeof<Example[]>
    printfn $"HasElementType is '{t.HasElementType}' for array types."

    // When you use Reflection Emit to emit dynamic methods and
    // assemblies, you can create array types using MakeArrayType.
    // The following creates the type 'array of Example'.
    let t = typeof<Example>.MakeArrayType()
    printfn $"HasElementType is '{t.HasElementType}' for array types."

    // When you reflect over methods, HasElementType is true for
    // byref, outref, and pointer parameter types. The following
    // gets the Test method, defined above, and examines its
    // parameters.
    let mi = typeof<Example>.GetMethod "Test"
    let parms = mi.GetParameters()
    let t = parms[0].ParameterType
    printfn $"HasElementType is '{t.HasElementType}' for ref parameter types."
    let t = parms[1].ParameterType
    printfn $"HasElementType is '{t.HasElementType}' for out parameter types."
    let t = parms[2].ParameterType
    printfn $"HasElementType is '{t.HasElementType}' for pointer parameter types."

    // When you use Reflection Emit to emit dynamic methods and
    // assemblies, you can create pointer and ByRef types to use
    // when you define method parameters.
    let t = typeof<Example>.MakePointerType()
    printfn $"HasElementType is '{t.HasElementType}' for pointer types."
    let t = typeof<Example>.MakeByRefType()
    printfn $"HasElementType is '{t.HasElementType}' for ByRef types."

Imports System.Reflection
Imports System.Runtime.InteropServices

Public Class Example

    ' This method is for demonstration purposes.
    Public Shared Sub Test(ByRef x As Integer, <Out> ByRef y As Integer)
    End Sub

    Public Shared Sub Main()
        ' All of the following display 'True'.

        ' Define an array, get its type, and display HasElementType. 
        Dim nums() As Integer = {1, 1, 2, 3, 5, 8, 13}
        Dim t As Type = nums.GetType()
        Console.WriteLine("HasElementType is '{0}' for array types.", t.HasElementType)

        ' Test an array type without defining an array.
        t = GetType(Example())
        Console.WriteLine("HasElementType is '{0}' for array types.", t.HasElementType)

        ' When you use Reflection Emit to emit dynamic methods and
        ' assemblies, you can create array types using MakeArrayType.
        ' The following creates the type 'array of Example'.
        t = GetType(Example).MakeArrayType()
        Console.WriteLine("HasElementType is '{0}' for array types.", t.HasElementType)

        ' When you reflect over methods, HasElementType is true for
        ' ref, out, and pointer parameter types. The following 
        ' gets the Test method, defined above, and examines its
        ' parameters.
        Dim mi As MethodInfo = GetType(Example).GetMethod("Test")
        Dim parms() As ParameterInfo = mi.GetParameters()
        t = parms(0).ParameterType
        Console.WriteLine("HasElementType is '{0}' for ref parameter types.", t.HasElementType)
        t = parms(1).ParameterType
        Console.WriteLine("HasElementType is '{0}' for <Out> parameter types.", t.HasElementType)

        ' When you use Reflection Emit to emit dynamic methods and
        ' assemblies, you can create pointer and ByRef types to use
        ' when you define method parameters.
        t = GetType(Example).MakePointerType()
        Console.WriteLine("HasElementType is '{0}' for pointer types.", t.HasElementType)
        t = GetType(Example).MakeByRefType()
        Console.WriteLine("HasElementType is '{0}' for ByRef types.", t.HasElementType)
    End Sub 

End Class

Observações

Por exemplo, Type.GetType("Int32[]"). HasElementType devolve true, mas Type.GetType("Int32"). HasElementType devolve false. HasElementType também retorna true para "Int32*" e "Int32&".

Se a corrente Type representa um tipo genérico, ou um parâmetro de tipo na definição de um tipo genérico ou método genérico, esta propriedade devolve falsesempre .

Ver também

• HasElementTypeImpl()
• IsArray
• IsPointer
• IsByRef
• GetElementType()
• GetType()