如何在PHP中创建一个静态变量来返回最后的数组索引?

I want to create a function which a static variable because I need to preserve the variable value between functions. The first way, this variable include the last index an array, and the value will be changed the second run. If I use count() to search the last array index, I get the following error: Parse error: parse error, expecting I want to create a function which a static vari