c# - How to overwrite next line after found line in text document -

here want 1 thing, take line value, found in text document , want overwrite x not on found line, on next line coming after found line

so if content is:

line1 line2 line3 line4 

and if string text = "line2"; code:

using system; using system.io;  namespace _03_0 {     class program     {         static void main(string[] args)         {             string text = "line2";              string text = file.readalltext("doc.txt");              text = text.replace(text, "x");              file.writealltext("doc.txt", text);                   }     } } 

i have result:

line1 x line3 line4 

but want result:

line1 line2  x line4 

i suggest using regular expressions this:

string filepath = @"doc.txt"; string mystr = "line2"; string content = file.readalltext(filepath); string pattern = string.format(@"(?<={0}\r\n).+?(?=\r\n)", mystr); regex r = new regex(pattern); file.writealltext(filepath, r.replace(content, "x")); 

p.s: you'll need import regularexpressions namespace:

using system.text.regularexpressions; 

hope helps :)

a side note: you can't use same variable name (text) twice.