Dotnet2.0中string 转 char *

String TO char *使用String的Chars[i]方法，该方法只能针对ascii码char at_cmd[1024] = {0};
String* _at_cmd = "at+system=wl phy_forcecal 1";
int at_cmd_len = _at_cmd->Length;
memset(at_cmd,0,1024);
for(i=0;i<at_cmd_len;i++)
{
    at_cmd[i] = _at_cmd->Chars[i]&0xff;
}Runtime::InteropServices::Marshal::StringToHGlobalAnsi
该函数返回值需要释放
Marshal::FreeHGlobalusing namespace System;
using namespace System::Runtime::InteropServices;
#include <iostream>                                                 // for printf
int main()
{
    // Create a managed string.
    String^ managedString = "Hello unmanaged world (from the managed world).";
    // Marshal the managed string to unmanaged memory.
    char* stringPointer = (char*) Marshal::StringToHGlobalAnsi(managedString ).ToPointer();
    printf("stringPointer = %s\n", stringPointer);
    // Always free the unmanaged string.
    Marshal::FreeHGlobal(IntPtr(stringPointer));
    return 0;
}PtrToStringChars转换为Unicode