This is a collection of questions that come up every now and then about syntax in PHP. This is also a Community Wiki, so everyone is invited to participate in maintaining this list.
It used to be hard to find questions about operators and other syntax tokens.¹
The main idea is to have links to existing questions on Stack Overflow, so it's easier for us to reference them, not to copy over content from …
是什么区别=,==和===？
我认为使用一个等号是声明一个变量,而两个等号用于比较条件,最后三个等号用于比较声明变量的值.