如何將 C# string[] 傳遞給 C char** 或 char[][]

Question

在 C/C++ 中我有

typedef char TDAStringType[256];

struct CMarketReqMarketDataField
{
    TDACharType         MarketType;                     
    TDACharType         SubscMode;                      
    TDAIntType          MarketCount;                    
    TDAStringType       MarketTrcode[20];   
    TDAStringType       ErrorDescription;               
}

看看成員MarketTrcode ，似乎有一個 string/ char *數組，但我需要通過 C# string[]前端將值傳遞給 C/C++ 中的這個結構，我該怎么做？ 使用 SWIG 4.0.2

Answer 1

用於 PInvoke 編組的等效 C# 結構將是

[StructLayout(LayoutKind.Sequential, CharSet = CharSet.Ansi)]
struct TDAStringType
{
    [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 256)]
    public string String;
}

[StructLayout(LayoutKind.Sequential, CharSet = CharSet.Ansi)]
struct CMarketReqMarketDataField
{
    public char MarketType;                     
    public char SubscMode;                      
    public int MarketCount;                    
    [MarshalAs(UnmanagedType.ByValArray, SizeConst = 20)]
    public TDAStringType[] MarketTrcode;
    [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 256)]
    public string ErrorDescription;
}