is substring of javascript code example
Example 1: javascript check if character exists in string
// With ES6 MDN docs .includes()
"FooBar".includes("oo"); // true
"FooBar".includes("foo"); // false
"FooBar".includes("oo", 2); // false (2 is the start position for the search)
// E: Not suported by IE - instead you can use the Tilde opperator ~ (Bitwise NOT) with .indexOf()
~"FooBar".indexOf("oo"); // -2
~"FooBar".indexOf("foo"); // 0
~"FooBar".indexOf("oo", 2); // 0 (parameter 2 is the start position for the search)
// Used with a number, the Tilde operator effective does ~N => -(N+1). Use it with double negation !! (Logical NOT) to convert the numbers in bools:
!!~"FooBar".indexOf("oo"); // true
!!~"FooBar".indexOf("foo"); // false
!!~"FooBar".indexOf("oo", 2); // false
Example 2: js .substring
let anyString = 'Mozilla'
// Displays 'M'
console.log(anyString.substring(0, 1))
console.log(anyString.substring(1, 0))
// Displays 'Mozill'
console.log(anyString.substring(0, 6))
// Displays 'lla'
console.log(anyString.substring(4))
console.log(anyString.substring(4, 7))
console.log(anyString.substring(7, 4))
// Displays 'Mozilla'
console.log(anyString.substring(0, 7))
console.log(anyString.substring(0, 10))
Example 3: cut string from string javascript
var ret = "data-123".replace('data-','');
console.log(ret); //prints: 123