c＃regexp，仅替换部分文本

Question

I have a text variable which can contain many ( (VAR=var_name )). I want to replace (( VAR=var_name )) by the var_name only in src= (so, no in href= for instance.

sText = "some text href=\"sometext((VAR=XXXX))sometext((VAR=YYYYY))\"
src=\"sometext((VAR=XXXX))sometext((VAR=YYYYY)) \" some text some text
href=\"sometext((VAR=XXXX))sometext((VAR=YYYYY))\"
src=\"sometext((VAR=XXXX))sometext((VAR=YYYYY))\" some text";

I want to get after replacing :

sText = "some text href=\"sometext((VAR=XXXX))sometext((VAR=YYYYY))\"
src=\"sometext**XXXX**sometext**YYYYY**\" some text some text
href=\"sometext((VAR=XXXX))sometext((VAR=YYYYY))\"
src=\"sometext**XXXX**sometext**YYYYY**\" some text";

Have you got an idea ?

JC

Answer 1

string srcPattern = @"src="".+?""";
string varPattern = @"\(\(VAR=(.+?)\)\)";

string result = Regex.Replace(sText, srcPattern,
    m => Regex.Replace(m.Value, varPattern, n => "**" + n.Groups[1].Value + "**"));

The first regular expression match the string src = "...". While the second regular expression replaces every statement in brackets on its value.