Problem with undefined Function

[lhua059]

hi there, in my php program , i have a function called extractDate(), when i open that file in a browser , its said that the function hasn't been defined, i don't see why ..can anyone tell me why? cheers!

extractDate( );

		function extractDate(){
			foreach ($DATE as $Selected_Date){
				$Date_Selected=array();

				if($Selected_Date==""){
					echo "You should select at least one day for your booking";
				}
				if($Selected_Date=="day1"){
					$Date_Selected[]=$preferDATE["day1"];
				}
				if($Selected_Date=="day2"){
					$Date_Selected[]=$preferDATE["day2"];
				}
				if($Selected_Date=="day3"){
					$Date_Selected[]=$preferDATE["day3"];
				}
				if($Selected_Date=="day4"){
					$Date_Selected[]=$preferDATE["day4"];
				}
				if($Selected_Date=="day5"){
					$Date_Selected[]=$preferDATE["day5"];
				}
			}

			echo count($Date_Selected);

		}

[Errant]

Because you are calling the function at the top of the page - before it has been defined by your script. It is like being asked a question you don't know the answer to till tomorrow!!

Otherwise everything looks fine. Corrected script:

function extractDate(){
                foreach ($DATE as $Selected_Date){
                    $Date_Selected=array();

                if($Selected_Date==""){
                    echo "You should select at least one day for your booking";
                }
                if($Selected_Date=="day1"){
                    $Date_Selected[]=$preferDATE["day1"];
                }
                if($Selected_Date=="day2"){
                    $Date_Selected[]=$preferDATE["day2"];
                }
                if($Selected_Date=="day3"){
                    $Date_Selected[]=$preferDATE["day3"];
                }
                if($Selected_Date=="day4"){
                    $Date_Selected[]=$preferDATE["day4"];
                }
                if($Selected_Date=="day5"){
                    $Date_Selected[]=$preferDATE["day5"];
                }
            }

            echo count($Date_Selected);

        } 

 extractDate( ); 

[Weedpacket]

You can call functions earlier in the file than where they are declared (otherwise you wouldn't be able to do recursion); so the code as posted is correct in that sense.

The code as posted does have errors in that $DATE and $preferDATE are undefined, which leads me to suspect that this isn't the real code. In which case, the problem with the real code is anyone's guess.

[Errant]

Ahh I see what you mean there 🙁 too much time hanging around Javascript spit, and as I was so excited to spot the 'error' I missed the obvious....... 😃

But I assume he is talking about a 'call to undefinded function' error, which wouldn't account for those missing variables would it?

[lhua059]

yeah Errant is right...i place the function call underneath the actual function then it works ..well i just look at the PHp manual , and it states there the function can be called even if the definition of the function is beblow the function call like:

executeFunction();
function executeFunction{
         some codes
}

now i have a question....if you have single Php file say booking.php, and you have the form data in it, and codes to process the form data something like that...how can u go back to the previous page if the user enter some incorrect info....i try using the <a href="booking.php" > ...it would return me the blank form page, like the one first display to the user....any idea i can do that? cheers

[Errant]

Fairly simple. Add the form data to the url, for example:

booking.php?field1=data1&field2=&data2

Then use the following code to 'GET' the relevant data from the url:

$data1 = $_GET['data1'];
$data2 = $_GET['data2'];

Then inside the form that gets displayed you need the following (assuming that it is straight coded and not echo'd from the php)

<form ... >
<INPUT type="text" id="field1" value="<? echo $data1; ?>" >
<INPUT type="text" id="field2" value="<? echo $data2; ?>" >
etc.....
</form>