Simple analysis of the use of PHP variable modifier static

A static variable exists only in a local function field, but its value is not lost when the program executes out of this scope. Take a look at the following example:

Copy Code code as follows:
function Test () {
static $a = 0;
$a + +;
echo $a;
}

Test ();//1
Test ();//2
Test ();//3
Note: Static variables can be declared according to the example above. If you assign a value to a declaration using the result of an expression, it can cause a parse error.

Copy Code code as follows:
static $a =0+1;
Static $a =sqrt (121);

Like the above assignment method will be an error, do not believe you try