2011-03-31 64 views
1

这工作:DateTime的方法链问题

$aWeekAfterDate = new DateTime(); 
$aWeekAfterDate->modify('+1 week'); 
$aWeekAfterDate->format('d.m.Y'); 

但这:

$aWeekAfterDate = new DateTime(); 
$aWeekAfterDate->modify('+1 week')->format('d.m.Y'); 

给了我这个错误:

Fatal error: Call to a member function format() on a non-object in ... on line ...

Fatal error (shutdown): Call to a member function format() on a non-object in ... on line ...

我已经看过了文档中的DateTime::modify方法它的回报值是这样的:

Returns the DateTime object for method chaining or FALSE on failure.

为什么方法链不起作用?

我使用PHP版本5.2.6。

回答

6

更新日志

Version Description 
5.3.0  Changed the return value on success from NULL to DateTime. 

于是久违的链接DateTime对象在PHP 5.3.0

+0

只介绍我怎么能不看到这一点。 – 2011-03-31 09:14:05

+0

容易被忽视,除非你之前被它蜇过 – 2011-03-31 09:32:04