c# - Finding/editing exact entry in file -

i'm trying make changes file , appear need regex. have following code:

    public delegate string updateaction(string contents);      public static void updatefile(string file, updateaction m)     {         string contents = "";         using (streamreader reader = new streamreader(file))             contents = reader.readtoend();          contents = m(contents);          using (streamwriter writer = new streamwriter(file))             writer.writeline(contents);     }      public static void updateproperty(string file, string objectname, string property, string value)     {         updatefile(file, delegate(string contents)         {             string propertypattern = "(\"" + property + "\".*?\")(.*?)(\")";             string pattern = "(\"?)" + objectname + "(\"?)(\n|\r|\r\n)(.*?){(.*?)}";             regexoptions options = regexoptions.singleline | regexoptions.multiline | regexoptions.ignorecase;             contents = new regex(pattern, options).replace(contents, (matchevaluator)(m => new regex(propertypattern, options).replace(m.value, delegate(match propertymatch)                 {                     string str = propertymatch.value;                     if (propertymatch.groups.count > 3)                     {                         str = propertymatch.groups[1] + value + propertymatch.groups[3];                     }                      return str;                 })));              return contents;         });     } 

an example file this:

"resource/hudlayout.res" {     circle     {         "visible"       "0"         "enabled"       "0"         "controlname"   "cexlabel"         "fieldname"     "circle"         "zpos"          "2"         "xpos"          "c-100"         "ypos"          "c-96"         "wide"          "201"         "tall"          "200"         "font"          "crosshairs34"  //crosshairsoutline34         "labeltext"     "9"         "textalignment" "center"             "fgcolor"       "crosshair"     }     circledot     {         "visible"       "0"         "enabled"       "0"         "controlname"   "cexlabel"         "fieldname"     "circledot"         "zpos"          "2"         "xpos"          "c-100"         "ypos"          "c-96"         "wide"          "201"         "tall"          "200"         "font"          "crosshairs34"  //crosshairsoutline34         "labeltext"     "8"         "textalignment" "center"             "fgcolor"       "crosshair"     }     quartercircle     {         "visible"       "0"         "enabled"       "0"         "controlname"   "cexlabel"         "fieldname"     "quartercircle"         "zpos"          "2"         "xpos"          "c-100"         "ypos"          "c-98"         "wide"          "201"         "tall"          "200"         "font"          "crosshairs34"  //crosshairsoutline34         "labeltext"     "w"         "textalignment" "center"             "fgcolor"       "crosshair"     } } 

when call updateproperty(@"c:\file.res", "circle", "enabled", "1"); it's matching circle , quartercircle , setting enabled property 1 both. i'm not great regex , wondering pattern should using catch object i'm searching for.

your regexes not formed correctly because forgot escape slashes (that why you'd rather use verbatim string literals when defining regex pattern), , main problem missing word boundaries \b.

here update should work (tested, , expected entry modified):

string propertypattern = @"(""\b" + regex.escape(property) + @"\b"".*?"")(.*?)("")"; string pattern = @"(""?)\b" + regex.escape(objectname) + @"\b(""?)(\r\n|\n|\r)(.*?){(.*?)}"; regexoptions options = regexoptions.singleline | regexoptions.ignorecase; 

i doubt need specify multiline flag since not using ^ , $ in patterns.

i added regex.escape(property) in case there special characters in argument pass (then there can problem \b, hope won't case).

also, match type of newline, need use (\r\n|\n|\r) longest part should come first, or never tested against.