xxxxxxxxxx
const str = "Hello World";
const searchString = "World";
if (str.includes(searchString)) {
console.log("String exists!");
} else {
console.log("String does not exist!");
}
xxxxxxxxxx
function isString(variable) {
return typeof variable === 'string';
}
// Example usage:
console.log(isString('Hello')); // true
console.log(isString(123)); // false
xxxxxxxxxx
it is better to check with isFinite() rather than typeof or isNAN()
check this:
var name="somename",trickyName="123", invalidName="123abc";
typeof name == typeof trickyName == typeof invalidName == "string"
isNAN(name)==true
isNAN(trickyName)==false
isNAN(invalidName)==true
where:
isFinite(name) == false
isFinite(trickyName)== true
isFinite(invalidName)== true
so we can do:
if(!isFinite(/*any string*/))
console.log("it is string type for sure")
notice that:
isFinite("asd123")==false
isNAN("asd123")==true