javascript check if string only contains letters code example

Example 1: how to check if a string has only alphabets in javascript

if (!/[^a-zA-Z]/.test(word))

Example 2: checking if a character is an alphabet in js

function isLetter(str) {
  return str.length === 1 && str.match(/[a-z]/i);
}

Example 3: javascript contains substring

var str = "We got a poop cleanup on isle 4.";
if(str.indexOf("poop") !== -1){
	alert("Not again");
}
//use indexOf (it returns position of substring or -1 if not found)

Example 4: js check if string contains character

"FooBar".includes("oo"); // true

"FooBar".includes("foo"); // false

"FooBar".includes("oo", 2); // false

Example 5: js check if string contains character

if (your_string.indexOf('hello') > -1)
{
  alert("hello found inside your_string");
}