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@NogDogNov 29.2006 — #Your test of...
I find a more robust method to verify that a value has been entered is:
This will avoid the unwanted notice if $_POST['var2'] is not set, and will not fail if the variable is set with a value of 0, or 0.0, or other non-empty strings that might be interpreted as FALSE.
isset() and about existing variable’s value
i ussually seen, for checking of existing variable value, people use to use isset() function, for checking form value or else.
isset() is always return true if the variable is exists, whether the value is exists or not. so just use variable name to check whether the value of given variable is set or not.
[code=php]
<?
if(isset($_POST[‘var1’])) print “var1 exists, but the value may not exists<br>”;
if($_POST[‘var2’]) print “var2 exists and the value of var is exists, value of var2 = ” . $_POST[‘var2’] . “<br>”;
?>
————–
<br>
<form action=”<?=$PHP_SELF?>” method=post>
var1 (check with isset()) <input type=”text” name=”var1″><br><br>
var2 (check by default) <input type=”text” name=”var2″><br><br>
<input type=”submit” value=”CHECK :.”>
</form>
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@NogDogNov 29.2006 — #Your test of...[code=php]
if($_POST['var2'])
[/code]...will fail (return FALSE) if, for instance, the user entered 0 (zero) as the value for that input. So it's possible in some situations that you might not want to use such a comparison. Also, depending on your error_reporting level, if $_POST['var2'] is not set for some reason, then that code will output a "notice" type error message, which could potentially be more than a cosmetic problem should it happens before a command that causes headers to be sent is executed.I find a more robust method to verify that a value has been entered is:
[code=php]
if(isset($_POST['var2'] and trim($_POST['var2']) !== '')
{
// OK
}
else
{
// error
}
[/code]This will avoid the unwanted notice if $_POST['var2'] is not set, and will not fail if the variable is set with a value of 0, or 0.0, or other non-empty strings that might be interpreted as FALSE.