String 转lpcstr

以下是两种将String转换为LPCSTR的方法：

1. 使用c_str()函数：

#include <iostream>
#include <string>

int main() {
    std::string str = "abcd";
    LPCSTR str1 = str.c_str();
    std::cout << "LPCSTR: " << str1 << std::endl;
    return 0;
}

2. 使用MultiByteToWideChar函数进行转换：

#include <iostream>
#include <string>
#include <Windows.h>

LPCWSTR str2LPCWSTR(std::string str) {
    int len = str.length();
    int lenbf = MultiByteToWideChar(CP_ACP, 0, str.c_str(), len, 0, 0);
    wchar_t* buffer = new wchar_t[lenbf];
    MultiByteToWideChar(CP_ACP, 0, str.c_str(), len, buffer, sizeof(wchar_t) * lenbf);
    buffer[len] = 0;
    return buffer;
}

int main() {
    std::string str = "abcd";
    LPCWSTR str1 = str2LPCWSTR(str);
    std::wcout << "LPCWSTR: " << str1 << std::endl;
    delete[] str1;
    return 0;
}