变量的差异[关闭]

Is $abc equal to $Abc in variables? I found two sites about lua and some programming language I don't understand. Others goes about posts on S.O. but about arrays in PHP. Anothers on other website goes about making strings uppercase or lowercase.

My real question is echo $Abc; equal to echo $abc;?

From the manual: http://www.php.net/manual/en/language.variables.basics.php

<?php
$var = 'Bob';
$Var = 'Joe';
echo "$var, $Var";      // outputs "Bob, Joe"
?>

So from this example $var was not overwitten by $Var.

So to answer your question $abc is not equal to $Abc

PHP variable names are case sensitive, so $abc is different from $Abc