解析-未捕获的TypeError：无法读取未定义的属性“ get”

Question

I am using Parse with javascript. I am trying to get an object and I am following the documentation closely. I still end up with the error

Uncaught TypeError: Cannot read property 'get' of undefined

$(document).ready(function(){

Parse.initialize("myInfo","myInfo");

var count = Parse.Object.extend('overallCount');
var myQuery = Parse.Query(count);

myQuery.get('Gqwk38uUYz', {  //HERE IS THE PROBLEM
    success: function(count) {
        // The object was retrieved successfully.
        var myCount = count.get('count');
        var updatedCount = myCount+1;

        $("#myNum").val(updatedCount);

        count.save(null, {
            success: function(count) {
                count.set('count', updatedCount);

                count.save();
            },
            error: function(model, error) {
                // This will be called.
                // error is an instance of Parse.Error with details about the error.
                if (error.code === Parse.Error.OBJECT_NOT_FOUND) {
                    alert("Uh oh, we couldn't find the object!");
                } else if (error.code === Parse.Error.CONNECTION_FAILED) {
                    alert("Uh oh, we couldn't even connect to the Parse Cloud!");
                }
            }
        });
    },
    error: function(object, error) {
        // The object was not retrieved successfully.
        // error is a Parse.Error with an error code and message.

    }
});
});

Answer 1

You are getting the error because myQuery is indeed undefined. You have to use "new" to create a query object. It's also good practice to capitalize class names:

var Count = Parse.Object.extend('overallCount');
var myQuery = new Parse.Query(Count);