Javascript check json output is empty

问题

If I have data in json like this :

{"items":[{"id":"2049","channel_code":"HBD","channel_name":"HBO HD"}]}

And if you search my data to the server could not find results like this :

{"items":[]}

Of output as above, how do I read that my data does not exist or is empty?

I have written some code that I got but have not found the results I want.

This code :

var data = { Name: "John Doe", Age: 25, Address: null, CityState: "Denver, CO" };
for (member in data) {
if (data[member] != null)
    //Do something
}

or

if (myObject == '') {
   alert('this object is empty');
}

Maybe someone can help me find a way out of this example. Please help

回答1:

To check whether your array is empty, just use the respective length property:

if ( data['items'].length < 1 ) {
   // it's empty
}

回答2:

You want to check if data.items.length > 0. Assuming

var data = {"items":[]};

回答3:

for (member in data) {
if (data[member] != null)
    //Do something
}

code inside for will not run because length of data is 0

if (myObject == '') {
   alert('this object is empty');
}

myObject wont be null because the object actually is there and its an empty array

you should check for myObject.length because its an empty array

来源：https://stackoverflow.com/questions/12932590/javascript-check-json-output-is-empty