JavaScript isEmptyObject: Three ways to check if an object is empty as I know:
1)
// jQuery implementation function isEmptyObject(obj) { var name; for ( name in obj ) { return false; } return true; }
2)
//Object.keys was only added in ECMAScript 5/JavaScript 1.8.5 function isEmptyObject(obj) { return Object.keys(obj).length === 0; }
To add compatible Object.keys support in older environments that do not natively support it, copy the following snippet:
if (!Object.keys) { Object.keys = (function () { var hasOwnProperty = Object.prototype.hasOwnProperty, hasDontEnumBug = !({toString: null}).propertyIsEnumerable('toString'), dontEnums = [ 'toString', 'toLocaleString', 'valueOf', 'hasOwnProperty', 'isPrototypeOf', 'propertyIsEnumerable', 'constructor' ], dontEnumsLength = dontEnums.length; return function (obj) { if (typeof obj !== 'object' && typeof obj !== 'function' || obj === null) throw new TypeError('Object.keys called on non-object'); var result = []; for (var prop in obj) { if (hasOwnProperty.call(obj, prop)) result.push(prop); } if (hasDontEnumBug) { for (var i=0; i < dontEnumsLength; i++) { if (hasOwnProperty.call(obj, dontEnums[i])) result.push(dontEnums[i]); } } return result; } })() };
3)
// Only work in Firefox function isEmptyObject(obj) { return obj.toSource() === "({})"; }