QString: replace white space behind "</tr>"

sonichy

I want a HTML indent function in QTextEdit.
Replace white space:

s = s.replace(QRegExp("[\\s]+"), "")

I want something like:

s = s.replace("</tr>white space", "</tr>\n")

KillerSmath

@sonichy
You must to scape the slash caracter \\/ in regular expression. Further you can use \\1 to insert the first captured group (</tr>) on replaced string.

See an example:

s.replace(QRegularExpression("(<\\/tr>)\\s"), "\\1\n");

sonichy

@KillerSmath Worked out, it is should be like these:

s = s.replace(QRegExp("[\\s]+(<td>)"), "\\1");   // delete white space before <td>
s = s.replace(QRegExp("[\\s]+(</td>)"), "\\1");   // delete white space before </td>
s = s.replace(QRegExp("(</tr>)[\\s]+"), "\\1\n");   // delete white space after </tr>

JonB

@KillerSmath

s.replace(QRegularExpression("(<\\/tr>)\\s"), "\\1\n");

Your answer is useful to the rest of the world, but for anyone reading this you have erroneously inserted a \\, before /tr, which should be removed.

KillerSmath

@JonB
Sorry but i used \\ to escape a backward slash to string because / in means "start or end of a regular expression" and it needs to be escaped.

Usage Example in regular expression
Forward slash explanation

JonB

@KillerSmath
I've used regular expressions in various languages for hundreds of years, and I've never escaped a /. Nor has / ever meant "start of regular expression" as per your sources! So I'm looking into this mystery (for me) now...!

I'm lost. This is all to do with "using / as the start of a regular expression". But isn't that JavaScript only? Every example on your references has /pattern/, that's not part of regular expressions. I think that's only because they are for using JS string.replace(/.../) "regular expression literal" syntax, no? Why would that apply to QRegularExpression?

fcarney

Or you could use the new C++ 11 literals:

R"((</tr>)[\s]+)"
R"delimiter((</tr>)[\s]+)delimiter"

No idea what they were smoking on the delimeter( version.

SGaist

Hi,

@KillerSmath what tools are you using for regular expressions ?

If you take VI for example, / are used to separate elements when doing a search and replace for example. Same with the sed command. With sed you can change the separation char if you need to use / in an expression.