Question

I have below test cases as input:

1. [This is my test] [This is my test] My name is xyz.

   Want Expected output as :
   [This is my test] My name is xyz.
   .

2. [This is my test] My name is xyz.
   Want Expected output as:
   My name is xyz.

For above test cases I want to replace only first occurrence of ‘[This is my test] ‘ with blank. I don’t want to replace second occurrence of match.

How do I resolve this using regex in JavaScript?

Thanks in advance.

ETA:

I just want to give more clarification that, i dont want to use hard coded value in regex , i want to use variable in regex.
Assume that [This is my test] is stored in one variable i.e. var defaultMsg = "[This is my test] ";

Answer 1

If the search pattern is in a string variable and can contain special characters, then it must be escaped. Like so:

var defaultMsg  = "[This is my test] ";

//-- Must escape special characters to use in a RegEx.
defaultMsg      = defaultMsg.replace (/([\!\$\(\)\*\+\.\/\:\=\?\[\\\]\^\{\|\}])/g, "\\$1")

var zRegEx      = new RegExp (defaultMsg, '');

var Str         = '[This is my test] [This is my test] My name is xyz.';

Str             = Str.replace(zRegEx, "");

console.log (Str);  //-- Or use alert()