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c++qtqstringchopqstringlist

Qt C++ How to chop a letter of QString that is member of a QStringList in 1 command

in my code I need to remove the last space(s) of a QString that is an element of a QStringlist DataColumns.

This is what I have:

  DataColumns[0] : "Time [ms]      "
  DataColumns[1] : "Position [m]"
  DataColumns[2] : "End Velocity [m/s]     "

This is what I want to have:

  DataColumns[0] : "Time [ms]"
  DataColumns[1] : "Position [m]"
  DataColumns[2] : "End Velocity [m/s]"

In a loop over i (element of DataColumn) and j (letter of element of DataColumn) I do the following and it works: 

 QStringList dataColums;
 QString A;
 ...
 A= dataColums[i];
 A.chop(1);
 dataColums[i] = A;

But when I try to put the last 3 lines into 1 command it doesn`t work. 

dataColums[i] = dataColums[i].chop(1);

Can anybody explain to my as to why that is? Thank you!

Solution

  • The function is declared like

    void QString::chop(int n);

    that is it has the return type void.

    So this statement

    dataColums[i] = dataColums[i].chop(1);

    is invalid. It looks like

    dataColums[i] = void;

    To remove white spaces from the both sides of a string you could use the member function trimmed.