Question

As far as I know jQuery has a function inArrary which is apply like the following

$.inArray(value, array); it return -1 if not in array 

However, this function only apply to value and is not suitable for the multidimension array

eg . fruit [ apple,orange]

For instance, if I have an array like this

eg. fruit [apple => [red,$1], orange => [orange,$5]]

I have to check whether a value exist (eg. banana) as the array key, are there any function appropriate in this case?

Answer 1

Arrays cannot have string keys in JavaScript. Only objects can.

If you want to see if an object contains has a key banana, you can simply test that it isn’t undefined:

if (myObject.banana != undefined) {

}

… or use hasOwnProperty, which may be better in cases when you may have initialized a property to undefined:

if (myObject.hasOwnProperty("banana")) {

}