string contains js

JavaScript
const string = "foo";
const substring = "oo";

console.log(string.includes(substring));var string = "foo",
    substring = "oo";

console.log(string.includes(substring));const string = "javascript";
const substring = "script";

console.log(string.includes(substring));  //truevar str = "Hello world, welcome to the universe.";
var n = str.includes("world");// 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); // falsevar str = "foobar"
var regex = /foo/g;
if (str.search(regex) !== -1) {
  alert("string conains foo!")
}
Source

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