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课设之百万数据文档存取
2022-07-07 12:12:00 【sinat_36789271】
其他类型转换成string类型:
string to_string (int val);
string to_string (long val);
string to_string (long long val);
string to_string (unsigned val);
string to_string (unsigned long val);
string to_string (unsigned long long val);
string to_string (float val);
string to_string (double val);
string to_string (long double val);
c_str()是Borland封装的String类中的一个函数,它返回当前字符串的首字符地址。当需要打开一个由用户自己输入文件名的文件时,可以这样写:ifstream in(st.c_str())
样例:
#include <iostream>
#include <fstream>
using namespace std;
int main()
{
string a="outputdsaftttt.txt";
ofstream output( a.c_str(), ios::out);
if( ! output )
{
cerr << "Open output file error!" << endl;
exit( -1 );
}
output.close();
return 0;
}
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Parameter keywords final, flags, internal, mapping keywords internal