check if var is string javascript code example
Example 1: is string javascript
function isString(value) {
return typeof value === 'string' || value instanceof String;
}
isString(''); // true
isString(1); // false
isString({}); // false
isString([]); // false
isString(new String('teste')) // true
Example 2: javascript is variable a string
if (typeof myVar === 'string'){
//I am indeed a string
}
Example 3: js check if variable is string
if (typeof myVar === 'integer'){
//I am indeed an integer
}
if (typeof myVar === 'boolean'){
//I am indeed a boolean
}
Example 4: if variable is string javascript
var booleanValue = true;
var numericalValue = 354;
var stringValue = "This is a String";
var stringObject = new String( "This is a String Object" );
alert(typeof booleanValue) // displays "boolean"
alert(typeof numericalValue) // displays "number"
alert(typeof stringValue) // displays "string"
alert(typeof stringObject) // displays "object"
Example 5: javascript check if var is string
if (typeof a_string === 'string') {
// this is a string
}
Example 6: check if value is a string javascript
let eventValue = event.target.value;
if (/^\d+$/.test(eventValue)) {
eventValue = parseInt(eventValue, 10);
}
//If value is a string, it converts to integer.
//Otherwise it remains integer.