How to delete new-line character in asctime in QString

Question

I am converting time_t to human readable format. For this purpose I am using asctime() function. However it is also mentioned in c++ references.

The string is followed by a new-line character ('\n') and terminated with a null-character.

I know that I can delete '\n' character if I use char pointer. Such as;

char * str; 
str(strlen(str)-1) = '\0'; // repleacing new-line char to null-char

However how can I delete new-line characther in QString? Here is my example;

    time_t rawtime;
    struct tm * timeinfo;
    QString strList;
    rawtime = 1430687052;
    timeinfo = localtime (&rawtime);
    strList += asctime(timeinfo);

EDIT:

I am creating report file, so that I have lots of '\n' char in my QString, thats why replacing all '\n' char to null pointer is not good idea.

Solution 1

There are 3 methods you will find useful:

bool QString::endsWith (const QChar &c, Qt::CaseSensitivity cs = Qt::CaseSensitive ) const;

QString::remove(int position, int n);

QString& replace(const QRegExp &rx, const QString & after)

Just remove last character and you're set. You can either use remove() or replace() with a regexp detecting \n at the end of the string.

Please be advised that internally QString uses 16-bit UTF character encoding.

If you like to operate on 8-bit characters, than you should use QByteArray and it's QByteArray::remove(int position, int n) method.

Solution 2

I would use QString::trimmed() function to remove all trailing and leading whitespace characters, such as '\t', '\n', '\v', '\f', '\r', and ' '. I.e.:

strList = strList.trimmed();

Solution 3

Tell me why you are using C standard API when you use Qt? You have great Qt API to handle dates.

QDateTime time;
uint rawtime = 1430687052;
time.setTime_t(rawtime);
QString humanDate = QLocale::system().toString(time, QLocale::ShortFormat);

---

QString::trimmed

Solution 4

AS vahancho already pointed out. trimmed is probably the best way to go.

From the documentation of trimmed:

Unlike simplified(), trimmed() leaves internal whitespace alone.

So for example:

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

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Comments

[goGud]

As I said in EDIT section, I creating report txt and xls file, that's why deleting all char is not good idea.. My aim is deleting only last '\n' char in QString.

[goGud]

Thank you I used remove function defining QRegExp and it solved my problem.

[vahancho]

The function does not delete all chars, but all whitespece chars from the start and the end.

[goGud]

actually I didnt know Qt has such ability.. I was writing application with limited time, thus I wrote it as fast as possible. +1 for informing such ability.