Sometimes when you make many functions in your PHP scripts. Then you need to check the real existence of the function you need. That’s why to check a function’s existence, you can write a little piece of code like the following:
<?php
if(function_exists(NameOfTheFunction))
{
echo "Function Exist";
}
else
{
echo "Function doesn't exist";
}
?>
NameOfTheFunction means your function's name. If your function is LoginCheck(). Then you need to write only LoginCheck. Just omitt the () symbol.
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