string should not contain special characters in javascript code example

Example 1: how to check for special characters in javascript

var format = /[!@#$%^&*()_+\-=\[\]{};':"\\|,.<>\/?]+/;

if(format.test(string)){
  return true;
} else {
  return false;
}

Example 2: does string contain special charactors javascript

var format = /[ `!@#$%^&*()_+\-=\[\]{};':"\\|,.<>\/?~]/;
//            ^                                       ^   
document.write(format.test("My@string-with(some%text)") + "<br/>");
document.write(format.test("My string with spaces") + "<br/>");
document.write(format.test("MyStringContainingNoSpecialChars"));