问题描述
我有这个C ++函式,
bool MyClass :: my_function(int num,TCHAR ** filepath)
我已将函数公开为
externC
{
__declspec(dllexport)bool MyFunction(int num,char * filepath [])
{
OutputDebugStringA( -MyFunction--);
TCHAR ** w_filepath =(TCHAR **)calloc(num,2 * sizeof(TCHAR **));
for(int i = 0; i {
OutputDebugStringA(filepath [i]);
int len = strlen(filepath [i])+ 1;
w_filepath [i] =(TCHAR *)calloc(1,len);
ctow(w_filepath [i],filepath [i]); // converted char to WCHAR
}
bool ret = MyClass.my_function(num,w_filepath);
OutputDebugStringA(End - MyFunction - );
free(w_filepath);
return ret;
}
}
我有C#封装为
[DllImport(MyDll.dll)]
public static extern bool MyFunction(int num,[MarshalAs(UnmanagedType.LPArray,ArraySubType = UnmanagedType.LPTStr)] string [] filepath);
在C#中,我调用Myfunction作为
string [] filepath = {D:\\samplefile\\abc.txt,D:\\samplefile\\def.txt}
MyFunction(2,filepath)
在C ++函数中,它只获取文件路径的第一个字符。
例如,从上面调用如果我使用
OutputDebugStringA
只会为第一个和第二个打印D.
/ p>
[MarshalAs(UnmanagedType.LPArray,ArraySubType = UnmanagedType.LPTStr)]
pre>
来自c#wrapper
中获取Access违规错误。
我将在
code> w_filepath [i] =(TCHAR *)calloc(1,len)
第二个档案。
请帮助我。
解决方案1) code> w_filepath [i] =(TCHAR *)calloc(1,len); - calloc需要大小(以字节为单位),因此应为
w_filepath [i] = (wchar_t *)calloc(1,len * sizeof(wchar_t));
2)c#中的数据来自wchar_t *不需要转换例程,应该将函数声明更改为
__ declspec(dllexport)bool MyFunction(int num,wchar_t * filepath [])
I've this C++ function,
bool MyClass::my_function(int num, TCHAR** filepath)
I've expose the function as
extern "C" { __declspec(dllexport) bool MyFunction(int num, char* filepath[]) { OutputDebugStringA("--MyFunction--"); TCHAR **w_filepath = (TCHAR **)calloc(num, 2* sizeof(TCHAR **)); for(int i = 0; i < num; i++) { OutputDebugStringA(filepath[i]); int len = strlen(filepath[i]) + 1; w_filepath[i] = (TCHAR *)calloc (1, len); ctow(w_filepath[i], filepath[i]); // converts char to WCHAR } bool ret = MyClass.my_function(num, w_filepath); OutputDebugStringA("End -- MyFunction --"); free(w_filepath); return ret; } }
I've C# wrapper as
[DllImport("MyDll.dll")] public static extern bool MyFunction(int num, [MarshalAs(UnmanagedType.LPArray, ArraySubType = UnmanagedType.LPTStr)] string[] filepath);
In C#, i call Myfunction as
string [] filepath = { "D:\\samplefile\\abc.txt", "D:\\samplefile\\def.txt"} MyFunction(2, filepath)
In C++ function, it gets only first character of filepath.For example, from above call if i print in C++ code using
OutputDebugStringA
it prints only D for both first and second.
If i remove
[MarshalAs(UnmanagedType.LPArray, ArraySubType = UnmanagedType.LPTStr)]
from c# wrapperI'll get Access violation error in
w_filepath[i] = (TCHAR *)calloc (1, len)
for second file.
Please help me.
解决方案1)
w_filepath[i] = (TCHAR *)calloc (1, len);
- calloc requires size in bytes, so it should bew_filepath[i] = (wchar_t *)calloc (1, len*sizeof(wchar_t));
2) data from c# comes as wchar_t*, so you don't need converting routines at all , and should change function declaration to
__declspec(dllexport) bool MyFunction(int num, wchar_t* filepath[])
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