qt - Reverse text file writing in QT

Question

How is it better to implement writing to QFile in reverse order, string by string. With use of seek(0) new string is written over old one.

Answer 1

你应该使用一个QStackQString。由于它是一个 LIFO（后进先出）容器，我认为这就是您要搜索的内容。

按下每个字符串，然后弹出所有字符串：

QStack<QString> stack;
stack.push("first string");
stack.push("second string");
stack.push("third string");

while (!stack.isEmpty())
{
   QString string = stack.pop();
}

编辑：（关于要写入的 2 个文件的评论中的新信息）

使用 aQvector存储所有 QString。然后在for循环中访问第一个和最后一个元素，将它们写入每个文件中。这可以这样做：

QVector<QString> vector;
vector.append("first string");
vector.append("second string");
vector.append("third string");

int size = vector.size();
for (int i=0; i<size; i++)
{
   QString string1 = vector[0]; // write it in one file
   Qstring string2 = vector[size-1-i]; // write it in another file
}

希望这能回答你的问题。

Answer 2

Read all the file. Save it to a vector of QStrings in the memory. Go trough the vector reversing all the strings and save this vector to the file again.