这可能有点俗气。你可以试试这个。

if (JSON.stringify(data).length === 2) {
   // Do something
}

不确定这种方法是否有任何缺点。

我想你说的空是指“没有自己的属性”。

// Speed up calls to hasOwnProperty
var hasOwnProperty = Object.prototype.hasOwnProperty;

function isEmpty(obj) {

    // null and undefined are "empty"
    if (obj == null) return true;

    // Assume if it has a length property with a non-zero value
    // that that property is correct.
    if (obj.length > 0)    return false;
    if (obj.length === 0)  return true;

    // If it isn't an object at this point
    // it is empty, but it can't be anything *but* empty
    // Is it empty?  Depends on your application.
    if (typeof obj !== "object") return true;

    // Otherwise, does it have any properties of its own?
    // Note that this doesn't handle
    // toString and valueOf enumeration bugs in IE < 9
    for (var key in obj) {
        if (hasOwnProperty.call(obj, key)) return false;
    }

    return true;
}

例子:

isEmpty(""), // true
isEmpty(33), // true (arguably could be a TypeError)
isEmpty([]), // true
isEmpty({}), // true
isEmpty({length: 0, custom_property: []}), // true

isEmpty("Hello"), // false
isEmpty([1,2,3]), // false
isEmpty({test: 1}), // false
isEmpty({length: 3, custom_property: [1,2,3]}) // false

如果你只需要处理ECMAScript5浏览器，你可以使用Object。getOwnPropertyNames而不是hasOwnProperty循环:

if (Object.getOwnPropertyNames(obj).length > 0) return false;

这将确保即使对象只有不可枚举的属性，isEmpty仍然会给您正确的结果。

快速联机'dictionary'-objects:

function isEmptyDict(d){for (var k in d) return false; return true}

funtion isEmpty(o,i)
{
    for(i in o)
    {
        return!1
    }
    return!0
}

function isEmpty( o ) {
    for ( var p in o ) { 
        if ( o.hasOwnProperty( p ) ) { return false; }
    }
    return true;
}

这是我的解决方案

function isEmpty(value) {
    if(Object.prototype.toString.call(value) === '[object Array]') {
        return value.length == 0;
    } else if(value != null && typeof value === 'object') {
        return Object.getOwnPropertyNames(value).length  == 0;
    } else {
        return !(value || (value === 0));
    }
}

解围球