How do I remove trailing whitespace from a QString?

Question

I want to remove all the trailing whitespace characters in a QString. I am looking to do what the Python function str.rstrip() with a QString.

I did some Googling, and found this: http://www.qtforum.org/article/20798/how-to-strip-trailing-whitespace-from-qstring.html

So what I have right now is something like this:

while(str.endsWith( ' ' )) str.chop(1); while(str.endsWith( '\n' )) str.chop(1); 

Is there a simpler way to do this? I want to keep all the whitespace at the beginning.

Answer 1

QString has two methods related to trimming whitespace:

• QString QString::trimmed() const
  Returns a string that has whitespace removed from the start and the end.
• QString QString::simplified() const
  Returns a string that has whitespace removed from the start and the end, and that has each sequence of internal whitespace replaced with a single space.

If you want to remove only trailing whitespace, you need to implement that yourself. Here is such an implementation which mimics the implementation of trimmed:

QString rstrip(const QString& str) {   int n = str.size() - 1;   for (; n >= 0; --n) {     if (!str.at(n).isSpace()) {       return str.left(n + 1);     }   }   return ""; } 

Answer 2

QString provides only two trimming-related functions. In case if they don't suit your needs, I'm afraid you need to implement your own custom trimming function.

QString QString::simplified () const
Returns a string that has whitespace removed from the start and the end, and that has each sequence of internal whitespace replaced with a single space.

QString str = "  lots\t of\nwhitespace\r\n "; str = str.simplified(); // str == "lots of whitespace"; 

QString QString::trimmed () const
Returns a string that has whitespace removed from the start and the end.

QString str = "  lots\t of\nwhitespace\r\n "; str = str.trimmed(); // str == "lots\t of\nwhitespace"