std::basic_ios<CharT,Traits>::rdstate

 

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iostate rdstate() const;

返回当前流错误状态。

参数

(无)

返回值

当前流错误状态。它是一个位掩码类型，可以是以下常量的组合

常量	解释
goodbit	无错误
badbit	不可恢复的流错误
failbit	输入/输出操作失败（格式化或提取错误）
eofbit	关联的输入序列已到达文件末尾

示例

运行此代码

#include <iostream>
#include <sstream>
 
int main()
{
    std::ostringstream stream;
 
    if (stream.rdstate() == std::ios_base::goodbit)
        std::cout << "stream state is goodbit\n";
 
    stream.setstate(std::ios_base::eofbit);
 
    // check state is exactly eofbit (no failbit and no badbit)
    if (stream.rdstate() == std::ios_base::eofbit)
        std::cout << "stream state is eofbit\n";
}

输出

stream state is goodbit
stream state is eofbit

参见

setstate	设置状态标志 (公共成员函数)
clear	修改状态标志 (公共成员函数)