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

 

C++

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void setstate( iostate state );

在当前已设置表之外，设置流错误状态标志 state 。实质上调用 clear(rdstate() | state) 。可能抛出异常。

参数

state

-

要设置的流错误状态标志。能为下列常量的组合： 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 关联的输出序列已抵达文件尾

返回值

（无）

示例

运行此代码

#include <iostream>
#include <sstream>
 
int main()
{
    std::ostringstream stream;
 
    if (!stream.fail()) {
        std::cout << "stream is not fail\n";
    }
 
    stream.setstate(std::ios_base::failbit);
 
    if (stream.fail()) {
        std::cout << "now stream is fail\n";
    }
 
    if (!stream.good()) {
        std::cout << "and stream is not good\n";
    }
}

输出：

stream is not fail
now stream is fail
and stream is not good

参阅

rdstate	返回状态标志 (公开成员函数)
clear	修改状态标志 (公开成员函数)