QT 查找文件中字符串并替换的问题

Question

QT控制台程序，如果需要匹配的字符串在首行的话，无法完成替换。麻烦各位帮忙看看。打印出来的debug显示已经完成替换了，但是首行无法写入。其他行就完全没问题。。。。。。QT环境是QT5.11.0.。。。。谢谢

#include <QtCore/QCoreApplication>
#include <QFile>
#include <QTextStream>
#include <QTextCodec>
QString str,str2;
int main(int argc, char *argv[])
{
    QCoreApplication a(argc, argv);

    QTextStream cin(stdin, QIODevice::ReadOnly);
    QTextStream cout(stdout, QIODevice::WriteOnly);

    QString strAll;
    QStringList strList;
    QFile readFile("F:/test.txt");
     if(readFile.open((QIODevice::ReadOnly|QIODevice::Text)))
    {
        QTextStream stream(&readFile);
        strAll=stream.readAll();
    }readFile.close();

    QFile writeFile("F:/test.txt");
    if(writeFile.open(QIODevice::WriteOnly|QIODevice::Text))
    {
       QTextStream stream(&writeFile);
       strList=strAll.split("\n");

       cout<<"input string"<<endl;
       cin>>str;

       cout<<"input string to replace"<<endl;
       cin>>str2;

       for(int i=0;i<strList.count();i++)
       {
                if(i==strList.count()-1)
                {
                    //最后一行不需要换行
                    stream<<strList.at(i);
                }
                else
                {
                    stream<<strList.at(i)<<'\n';
                }
               //cout<<strList.at(i)<<endl;

        strList.replaceInStrings(str,str2);
#if 0
           if(strList.at(i).contains(str))
           {

               //QString tempStr=strList.at(i);
               strList.replaceInStrings(str,str2);
               cout<<strList.at(i)<<endl;

               stream<<'\n';

               i++;
           }
#endif
       }
    }
       writeFile.close();
}

Answer 1

strList.replaceInStrings(str,str2); 放到for循环外面就可以了。