function check string alert javascript code example

Example 1: 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 2: 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.