如何在C＃中的C結構寫的指針

Question

我在C以下結構：

typedef struct 
{ 
    int mode; 
    unsigned char *fs;//a pointer to sbyte[16] 
    unsigned char *flist;//a pointer to sbyte[128] 
    unsigned char *ival;//a pointer to sbyte[8] 
    unsigned char *ctx;//a pointer to sbyte[8] 
    int fin; 
} mStruct; 

，我需要它寫在C＃。我試圖將其定義爲：

[StructLayout(LayoutKind.Sequential,Pack=1)] 
public struct avGostParam 
{ 
    public int mode;//a mode 
    public IntPtr fs;// does char* converts to IntPtr? 
    public IntPtr flist;//does char* converts to IntPtr? 
    public IntPtr ival;//does char* converts to IntPtr? 
    public IntPtr ctx;//does char* converts to IntPtr? 
    public int fin; 
} 

但這是錯誤的方法。你能幫我翻譯成C＃嗎？

Answer 1

在結構中需要fixed arrays。

試試這個例子，其中只有字段fs被視爲通過Fs屬性進行管理的字符串轉換。

public unsafe struct avGostParam 
{ 
    public int mode; 
    public fixed char fs[16]; 
    public fixed char flist[128]; 
    public fixed char ival[8]; 
    public fixed char ctx[8]; 


    public string Fs 
    { 
     get 
     { 
      fixed(char* ptr=fs) 
      { 
       return GetString(ptr, 16); 
      } 
     } 

     set 
     {     
      fixed(char* ptr=fs) 
      { 
       SetString(ptr, 16, value); 
      } 
     } 
    } 

    private static string GetString(char* ptr, int length) 
    { 
     char[] result=new char[length]; 
     for(int i=0; i<length; i++) 
     { 
      result[i]=ptr[i]; 
     } 
     return new string(result); 
    } 
    private static void SetString(char* ptr, int length, string value) 
    { 
     if(value.Length<length) 
     { 
      value=value.PadRight(length); 
     } 
     char[] items=value.ToCharArray(); 
     for(int i=0; i<length; i++) 
     { 
      ptr[i]=items[i]; 
     }    
    } 
} 

unsafe class Program 
{ 
    static void Main(string[] args) 
    { 
     var av=new avGostParam(); 

     av.Fs="ABCDEF"; 

     char* ptr=av.fs; 
     for(int i=0; i<16; i++) 
     { 
      Console.Write(av.fs[i]); 
     } 
    } 
} 

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