#Non

iOS内存管理--nonatomic,assign,copy,retain

nonatomic:非原子性访问,不加锁进行同步,多线程并发访问会提高性能。如果不加此属性,默认是原子性访问。assign:简单赋值,不更改引用计数。一般用于基本数据类型。copy:在系统生成的setter方法中,对加了此属性的指针先释放旧值,然后赋予指针传入的新值的拷贝,拷贝工作由copy方法执行。对应的对象必须实现...

tp5分页注意,分页生成的ul class是pagination,有些模板可能将pagination定义为display:none

今天在调用分页时总是无法显示,查看网页源代码是正常的,后来发现是在css文件里将pagination定义为display:none,所以无法显示...

What is the difference between Clustered and Non-Clustered Indexes in SQL Server?

Fromthediscussionwefindfollowingdifferencesbetweenclusteredandnon-clusteredindexes.Therecanbeonlyoneclusteredindexpertable.However,youcancreatemultiplenon-clust...

****Call to a member function item() on a non-object

APHPErrorwasencounteredSeverity:ErrorMessage:Calltoamemberfunctionitem()onanon-objectFilename:libraries/Qiniu_utils.phpLineNumber:64Backtrace: 修改方法:在model和...
首页上一页...1516171819下一页尾页