Problem with function

Client Joined: Oct 07, 2003 Posts: 735 Location: Ohio

Here is the issue.

I have some code in a page that gathers my team_id and tid and then that calls a function to check if a team already exist on that tid. If a enemy team exist then I get forwarded to the attack page.

Like so.

Code:

checkmove($tid, $team_id); //Check to see if enemy exist on territory


      if ($enemy = TRUE) {


      Header("Location: modules.php?name=Campaign&file=Attack&team_id=$team_id"); 


      }else{ //No enemy occupies territory


      echo "<P><font color=RED size=6><center>Movement Orders Have Been Sent!</center></font></p>";


      echo "<P><font color=RED size=5><center>...Redirecting</center></font></p>";


      


      }

And here is the function that checks.

Code:

//Check if enemy exist on territory if so attack


function checkmove($tid, $team_id){


require_once("mainfile.php");


$module_name = basename(dirname(__FILE__));


include_once("modules/$module_name/language/lang-english.php");


global $db, $prefix, $module_name, $admin_file;


define('INDEX_FILE', true);


$index = 1;





 //Find the value of the division ID. 


  $sql = "SELECT div_id FROM " . $prefix . "_tc_teams WHERE team_id ='$team_id'"; 


  $result = $db->sql_query($sql); 


  $mydiv = $db->sql_fetchrow($result);


  $div_id = $mydiv['div_id']; 





//Look for enemy teams that may be on territory


$sql = "SELECT * FROM " . $prefix . "_tc_teams WHERE tid ='$tid' AND div_id != '$div_id'";


$result = $db->sql_query($sql); 


$enemy = FALSE;


   if ($db->sql_numrows($result) > 0) {


$enemy = TRUE; //Enemy exist on territory


}


 return $enemy; 


}

The $enemy should return True or False.

The problem is that first I manually verify that no other team occupies that tid, then make my move. I want to ensure the code is functioning correctly.

The result is it goes to the attack page but no enemy team is displayed. There is no enemy team dispayed because no other team_id occupies that tid so instead it should have just let me move and said this

Movement Orders Have Been Sent!

Here is a screenie:

I'm pretty sure my return code is working, but don't understand where I went wrong.

Evil or Very Mad

grrrrr.

I hate functions, but the only way to learn how to use them is to try.

registered · Posted: Fri Dec 08, 2006 4:09 pm

It doesn't look like checkmove is actually returning the proper variable. It should be put the checkmove return value into the $enemy variable like so

Code:




      $enemy = checkmove($tid, $team_id); //Check to see if enemy exist on territory


      if ($enemy = TRUE) {

Posted: Fri Dec 08, 2006 9:01 pm

Didn't help. I'm still getting the same thing.

Posted: Fri Dec 08, 2006 10:31 pm

Well I would guess its your SQL query then

Go ahead and echo out that SQL command and try it in phpMyAdmin, make sure you get what you think you should be getting

Code:




$sql = "SELECT * FROM " . $prefix . "_tc_teams WHERE tid ='$tid' AND div_id != '$div_id'"; 


echo $sql;


die();

Posted: Sat Dec 09, 2006 8:54 am

The echo displayed the following.

SELECT * FROM nuke_tc_teams WHERE tid ='36' AND div_id != '1'

Posted: Sat Dec 09, 2006 9:07 am

My 2 cents, just make MYSQL error checking part of your programs from the beginning and you can save a lot of time and a lot of posts. Stuff your query into a variable ... say $sql and then do a if(!result)) mysql_query($sql) and if the result doesn't return successful then do an echo like:

Code:

 echo 'sql failed . <br />';


            echo 'query was ' . $sql . '<br />';


            echo mysql_errno() . '<br />';


            echo mysql_error() . '<br />';


            die();

It's awfully easy to make an error in a query and you won't have any idea unless you check and echo out the errno and error message and I find it helps to have the actual sql it was trying to execute right on the screen with it.

Posted: Sat Dec 09, 2006 4:48 pm

I've done that and added error checking.

I also put this in to see what happens on my move.php page after it calls the function.

Code:

$enemy = checkmove($tid, $team_id); //Check to see if enemy exist on territory 


echo $enemy; 


die();

Nothing is displayed on move,php from the echo. $enemy contains nothing even tho in my function I am getting a result.

Here is what I'm trying to do in my move.php:

Code:

if ($op == "Move") {               


      $team_id = $_POST['team_id'];


      $tid = $_POST['tid'];      


      $action = 'Move';


      $dteam_id = 'N/A';      





      $sql = "UPDATE " . $prefix . "_tc_teams SET


      tid = '$tid'


      WHERE team_id = '$team_id'";





      $result = $db->sql_query($sql);   


      if (!$result) {


         echo("<p><font color=RED size=6><center>Error performing move. Data has not been sent!</center></font></p>");      


      }      


      





      // Post data to tracking table   


      $result1 = $db->sql_query ("INSERT INTO " . $prefix . "_eto_tracking (log_id, ateam_id, dteam_id, tid, move_dt, action)".


         "VALUES ('NULL','$team_id','$dteam_id','$tid',CURRENT_TIMESTAMP(),'$action')");


      


      //Update Fuel Points in lookup table.


      $rp_id = '1'; // Fuel Resource point ID


      $r_points = '-1'; //deducted fuel point for move


      $rp_details = 'Burned Fuel Moving on Map'; //Details


      $result2 = $db->sql_query ("INSERT INTO " . $prefix . "_eto_rpoints_lkup (pid, rp_id, rpoint_dt, team_id, r_points, rp_details)".


         "VALUES ('NULL', '$rp_id',CURRENT_TIMESTAMP(),'$team_id','$r_points', '$rp_details')");


      


      


      $enemy = checkmove($tid, $team_id); //Check to see if enemy exist on territory 


      echo $enemy; 


      die(); 





      if ($enemy = TRUE) { 








//      checkmove($tid, $team_id); //Check to see if enemy exist on territory


//      if ($enemy = TRUE) {


      Header("Location: modules.php?name=Campaign&file=Attack&team_id=$team_id"); 


      }else{ //No enemy occupies territory


      echo "<P><font color=RED size=6><center>Movement Orders Have Been Sent!</center></font></p>";


      echo "<P><font color=RED size=5><center>...Redirecting</center></font></p>";


      


      }   





}

And my function:

Code:

//Check if enemy exist on territory if so attack


function checkmove($tid, $team_id){


require_once("mainfile.php");


$module_name = basename(dirname(__FILE__));


include_once("modules/$module_name/language/lang-english.php");


global $db, $prefix, $module_name, $admin_file;


define('INDEX_FILE', true);


$index = 1;





 //Find the value of the division ID. 


  $sql = "SELECT div_id FROM " . $prefix . "_tc_teams WHERE team_id ='$team_id'"; 


  $result = $db->sql_query($sql); 


  $mydiv = $db->sql_fetchrow($result);


  $div_id = $mydiv['div_id']; 





//Look for enemy teams that may be on territory


$sql = "SELECT * FROM " . $prefix . "_tc_teams WHERE tid ='$tid' AND div_id != '$div_id'";


$result = $db->sql_query($sql); 





if (!$result) {


   echo 'sql failed . <br />'; 


            echo 'query was ' . $sql . '<br />'; 


            echo mysql_errno() . '<br />'; 


            echo mysql_error() . '<br />'; 


            die(); 


}





$enemy = FALSE;


   if ($db->sql_numrows($result) > 0) {


$enemy = TRUE; //Enemy exist on territory


}


 return $enemy; 


}

Posted: Sun Dec 10, 2006 9:47 pm

Okay, so the only way $enemy returns true is if this query executes

Code:




$sql = "SELECT * FROM " . $prefix . "_tc_teams WHERE tid ='$tid' AND div_id != '$div_id'";

And it returns more than 0 rows

Code:




if ($db->sql_numrows($result) > 0) {

There must be some logical problem in your code, perhaps it is not passing the right $tid or $div_id

Posted: Mon Dec 11, 2006 8:40 am

But the echo of my $sql variable displayed

Code:

SELECT * FROM nuke_tc_teams WHERE tid ='36' AND div_id != '1'

Which says to me that both tid and div_id are correct and contain the proper values.

I ran another test in the SQL pane

SELECT * FROM nuke_tc_teams WHERE tid ='19' AND div_id !='1'

which returned an emty set as it should.

But this in my function

Code:

$enemy = FALSE;


   if ($db->sql_numrows($result) > 0) {


$enemy = TRUE; //Enemy exist on territory


}


echo 'query was ' . $enemy . '<br />';

returns "query was" and enemy is blank

Is my problem that it is returning an empty set versus returning a 0?

Posted: Mon Dec 11, 2006 8:53 am

I'm far from an expert but I'm just wondering why in one snippet you are assigning $enemy to a function

Code:

$enemy = checkmove($tid, $team_id);

and then elsewhere you are assigning it as a logic True/False.

Posted: Mon Dec 11, 2006 9:08 am

He's talking about two different pieces of code Guardian .. using the same variable name $enemy inside the function as well as outside. Certainly should work fine

My q: why do you need all this code after the function definition

Code:




function checkmove($tid, $team_id){


require_once("mainfile.php");


$module_name = basename(dirname(__FILE__));


include_once("modules/$module_name/language/lang-english.php");

---------------------------

Alright, I see where the error is, your conditional here is wrong

Code:




if ($enemy = TRUE) { 





SIMPLY CHANGE TO





if ($enemy) {

Posted: Mon Dec 11, 2006 9:49 am

Also, and I had to confirm this for myself, try this little bit of code and see what the results are:

Code:

<?php


   $test = FALSE;


   echo 'value of  test ' . $test . '<br>';


?>





and i know I didn't close the br :)

Posted: Mon Dec 11, 2006 10:01 am

Code:

if ($enemy = TRUE) { 





SIMPLY CHANGE TO 





if ($enemy) {

This was the fix. Thanks Evaders. I don't know why I had all that in my function. I know at one time I had my globals outside of the function and was getting member not found errors. Maybe that is why I put all that there.

Posted: Mon Dec 11, 2006 11:12 am

One last question on this topic.

If I use the exit() at the end of this code I loose my right blocks. How do I avoid this but still kill the rest of the page from displaying.

Code:

$enemy = checkmove($tid, $team_id); //Check to see if enemy exist on territory


if ($enemy) {


   exit();


}else{


Opentable();


echo"<center><h3><b>" . _ATTACKTEAMS. "</b></h3></center><br><br>"


."<center><b><font color=RED size=4> There are no enemy forces positioned on your territory! </font></b></center><br><br>"


."<center><b> Your team is not in a position to attack at this time! </b></center><br><br>"


."<center><b> Move your team to a territory and engage enemy forces! </b></center><br><br>"


."<br>";


Closetable();


exit();


}

Posted: Mon Dec 11, 2006 12:51 pm

You don't need an exit() command unless you want the PHP script to immediately stop.
Just use the proper if statements to show whatever content needs to be displayed.

If there really is a reason you need to break the flow of your program, and still display right blocks, you can immediately pass the file to footer.php and that will close things out

Code:




include('footer.php');