javascript null conditional expression

Possible Duplicate:
null coalescing operator for javascript?

In C#, you can do this:

var obj = newObject ?? defaultObject;

That says assign newObject to obj if not null else assign defaultObject . How do I write this in javascript?

---

While it's considered an abusage, you can do the following:

var obj = newObject || defaultObject;

Note that if newObject is of any falsy value (such as 0 or an empty string), defaultObject will be returned as the value of obj . With this in mind, it may be preferred to use either the ternary operator or a standard if-statement.

var obj = ( "undefined" === typeof defaultObject ) ? defaultObject : newObject ;

链接地址: http://www.djcxy.com/p/73356.html

上一篇: 相当于JavaScript的JavaScript？ 运算符在C＃中

下一篇: javascript null条件表达式