Jeśli String JavaScript
if (typeof myVar === 'string') { /* code */ };
Batman
if (typeof myVar === 'string') { /* code */ };if (typeof myVar === 'string' || myVar instanceof String)
// it's a string
else
// it's something elseif (typeof myVar === 'string'){
//I am indeed a string
}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.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