javascript null or empty

When a database field is set to NULL, the phone side will return null by default, and if I want to make the phone return empty, I have to make a judgment. 1, if I want to let the mobile phone end is empty, do not judge, table field default should be

False, zero, null, undefined, and empty string objects in Javascript In Javascript, We often come into contact with the five special objects mentioned in the question -- false, 0, empty string, NullAnd undefined. These objects are easy to use

In JavaScript, we are often exposed to the 5 more special objects mentioned in the topic--false, 0, empty strings, null, and undefined. These objects are easy to use, so you have to be careful when you use them.Type detectionLet's come down and see

First, the difference between null and undefined:Executes typeof on declared but uninitialized and undeclared variables, returning "undefined".Null represents an empty object pointer, and the typeof operation returns "Object".Generally do not

http://blog.csdn.net/yiluoak_47/article/details/7766760First, the difference between null and undefined:Executes typeof on declared but uninitialized and undeclared variables, returning "undefined".Null represents an empty object pointer, and the

In JavaScript, we are often exposed to the 5 more special objects mentioned in the topic-false,0, empty strings ,null , and undefined . These objects are easy to use, so you have to be careful when you use them.Type detectionLet's come down and see

In JavaScript, we are often exposed to the 5 more special objects mentioned in the topic--false, 0, empty strings, null, and undefined. These objects are easy to use, so you have to be careful when you use them.Type detectionLet's come down and see

In JavaScript, we are often exposed to the 5 more special objects mentioned in the topic--false, 0, empty strings, null, and undefined. These objects are easy to use, so you have to be careful when you use them.Type detectionLet's come down and see

Transferred from: http://blog.csdn.net/yiluoak_47/article/details/7766760First, the difference between null and undefined:Executes typeof on declared but uninitialized and undeclared variables, returning "undefined".Null represents an empty object

First of all, the difference between null and undefined: Performs typeof on declared but uninitialized and undeclared variables, and returns "undefined". Null represents an empty object pointer, and the typeof operation returns "Object". It is