Escape "%" symbol when calling CString::FormatV

Question

I'm using var args in a file i/o function. It works fine unless the string which is wanting to be outputted contains a % and there are no additional arguments. E.g. the string <name px=100% /> would cause the issue, as an example. The code is roughly as follows:

void OutV(CString s, va_list args)
{
    CString formatted;
    formatted.FormatV(str, args);

    // Do stuff with formatted....
}

Is there a way that I could make it so that having a % symbol does not cause a problem. Ideally I'd like it inside of the OutV function above so that it only has to be in one place.

I can't do a simple replace all % with %% as then if there is a %d in there then that still needs to be substituted as an integer.

I can't do a simple replace all % with %% as then if there is a `%d` in there then that still needs to be substituted. — Luke, Dec 08 '14 at 14:51

wilx · Accepted Answer · 2014-12-08T14:57:16.397

1

Make sure your literal format strings escape the percent sign by doubling it: %%.

You might also want to consider using something like

OutV(CString("%s"), "<name px=100% />");

UPDATE

I can't do a simple replace all % with %% as then if there is a %d in there then that still needs to be substituted.

You need to piece things together more carefully. e.g.,

OutV(CString("%s%d%s"), "<name px=", 100, "% />");

edited Dec 08 '14 at 14:57

answered Dec 08 '14 at 14:51

wilx

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I've edited the OP: "I can't do a simple replace all % with %% as then if there is a %d in there then that still needs to be substituted" – Luke Dec 08 '14 at 14:52

Escape "%" symbol when calling CString::FormatV

1 Answers1

UPDATE