How can I convert QVariant to QString and vice versa in Qt?

Question

How can I convert QVariant to QString and Vice versa?

Thanks

Paul Wintz · Accepted Answer · 2018-09-11 21:55:05Z

81

From string:

QString qs;
QVariant qv(qs);

To string:

QString qs = qv.toString();

Tip: reading the help helps.

Paul Wintz

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answered Aug 29, 2011 at 10:24

hamstergene

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toString() does NOT return the value in the QVariant as a QString but rather describes the QVariant in a way that might be more suitable for debugging. I have found that QVariant::value<QString>() or QVariant::convert(QVariant::QString) seem to be more helpful, because they return the actual value in the QVariant.
– Mr. Developerdude
Commented Apr 3, 2016 at 1:52
3

@LennartRolland the code example in the docs explicitly states value<QString>() is the same as toString(). They both use canConvert() and convert() internally.
– hamstergene
Commented Apr 3, 2016 at 9:16
@hamstergene toString() appears to have begun working in qt 4.8; in qt 4.7, value<QString>() works, while toString() does not. So for this kind advice and compatibility, value<QString>() makes for a better general statement, unless qualified by version.
– fyngyrz
Commented Oct 17, 2016 at 22:43
2

@hamstergene I thought the help is SO.
– Liviu
Commented Mar 27, 2017 at 12:29
This does not work for certain types. For instance, when the QVariant contains a QStringList, .toString() returns a null string.
– Thomas Klier
Commented Aug 1, 2023 at 10:29

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