javascript replace part of string code example

Example 1: javascript replace string

var str = "JavaScript replace method test";
var res = str.replace("test", "success");  
//res = Javscript replace method success

Example 2: javascript replace

var res = str.replace("find", "replace");

Example 3: replace all occurrences of a string in javascript

const p = 'dog dog cat rat';

const regex = /dog/gi;

console.log(p.replace(regex, 'cow'));
//if pattern is regular expression all matches will be replaced
//output: "cow cow cat rat"

Example 4: replace in string javascript

const p = 'hello world ! hello everyone ! ';

const regex = /hello/gi;

console.log(p.replace(regex, 'good morning'));
// expected output: "good morning world ! good morning everyone !"

console.log(p.replace('hello', 'good evening'));
// expected output: "good evening world ! hello everyone !"

Example 5: replace javascript

// Replace with no modifiers
let newText = startText.replace("yes", "no")
console.log(newText)  // "Yes, I said no, it is, yes."

// Replace with 'g'-global modifier
newText = startText.replace(/yes/g, "no")
console.log(newText)  // "Yes, I said no, it is, no."

// Replace with modifiers 'g'-global and 'i'-case insensitive
newText = startText.replace(/yes/gi, "no")
console.log(newText)  // "no, I said no, it is, no."