php global_PHP tutorial

$A="hello";

function print_a(){

$A="php&mysql";
global $A;
$A="mytest";
echo $A;
}

echo $A;
echo "
";
print_a();
echo "
";
echo $A;
?>

Output result:

hello
mytest
mytest

I was a little confused at first, but this program and the output clearly illustrate what global.

In the function definition, after declaring global, the variable becomes global. Of course, even if a local variable with the same name has been defined in the function, "it" is no longer used, and it becomes a reference to the previously defined variable. .

Excerpted from Liu Chuan

http://www.bkjia.com/PHPjc/478330.htmlwww.bkjia.comtruehttp: //www.bkjia.com/PHPjc/478330.htmlTechArticle?php $A=hello; function print_a(){ $A=phpmysql; global $A; $A= mytest; echo $A; } echo $A; echo br; print_a(); echo br; echo $A; ? Output result: hello mytest mytest There is a little bit at the beginning...