Answers for "js if function exists"

javascript check if function exists

//check if sayHello() function exists
if (typeof sayHello === "function") { 
    // This function exists
}

js check if function exists

if (typeof yourFunctionName == 'function') { 
  yourFunctionName(); 
}

javascript check if function exists

if (typeof sourceObj.someMethod === "function") { 
    // you are safe using the method
  	sourceObj.someMethod();
}

function exists javascript

How to check if function exists in JavaScript?