IntPtr.Add(IntPtr, Int32) 方法

定義

將位移加入帶正負號的整數。

public:
 static IntPtr Add(IntPtr pointer, int offset);
public static IntPtr Add (IntPtr pointer, int offset);
static member Add : nativeint * int -> nativeint
Public Shared Function Add (pointer As IntPtr, offset As Integer) As IntPtr

參數

pointer
IntPtr

nativeint

要加入位移的帶正負號整數。

offset
Int32

要加上的位移。

傳回

IntPtr

nativeint

新的帶正負號的整數,反映 offset 新增至 pointer 的 。

範例

下列範例會具現化 IntPtr 指向十個元素陣列開頭的物件,然後呼叫 Add 方法來逐一查看陣列中的元素。

using System;
using System.Runtime.InteropServices;

public class Example
{
   public static void Main()
   {
      int[] arr = { 2, 4, 6, 8, 10, 12, 14, 16, 18, 20 };
      unsafe {
         fixed(int* parr = arr) {
            IntPtr ptr = new IntPtr(parr);
            // Get the size of an array element.
            int size = sizeof(int);
            for (int ctr = 0; ctr < arr.Length; ctr++)
            {
               IntPtr newPtr = IntPtr.Add(ptr, ctr * size);
               Console.Write("{0}   ", Marshal.ReadInt32(newPtr));
            }
         }
      }
   }
}
// The example displays the following output:
//       2   4   6   8   10   12   14   16   18   20
#nowarn "9"
open System
open System.Runtime.InteropServices
open FSharp.NativeInterop

[<EntryPoint>]
let main _ =
    let mutable arr = 
        [| 2; 4; 6; 8; 10; 12; 14; 16; 18; 20 |]
    
    use parr = fixed arr
    
    let ptr = NativePtr.toNativeInt parr

    // Get the size of an array element.
    let size = sizeof<int>
    for i = 0 to arr.Length - 1 do
        let newPtr = IntPtr.Add(ptr, i * size)
        printf $"{Marshal.ReadInt32 newPtr}   "
    0

// The example displays the following output:
//       2   4   6   8   10   12   14   16   18   20
Imports System.Runtime.InteropServices

Module Example
   Public Sub Main()
      Dim arr() As Integer = { 2, 4, 6, 8, 10, 12, 14, 16, 18, 20 }
      Dim ptr As IntPtr = Marshal.UnsafeAddrOfPinnedArrayElement(arr, 0)

      For ctr As Integer= 0 To arr.Length - 1
         Dim newPtr As IntPtr = IntPtr.Add(ptr, ctr * Len(arr(0)))
         Console.Write("{0}   ", Marshal.ReadInt32(newPtr))
      Next
   End Sub
End Module
' The example displays the following output:
'       2   4   6   8   10   12   14   16   18   20

備註

如果結果太大而無法在執行進程中表示為帶正負號的整數,則 Add 方法不會擲回例外狀況。 相反地,加法作業會在未核取的內容中執行。

不支援運算子多載或自訂運算子的語言可以使用此方法,將位移新增至指標的值。

適用於

另請參閱