Populate HTML SELECT using mysql and php_问答_开发者

Populate HTML SELECT using mysql and php

开发者 https://www.devze.com 2023-03-28 14:23 出处：网络

what is the best, tidiest way to populate a html select tag with items from the database? For example, if I have the following php:

what is the best, tidiest way to populate a html select tag with items from the database?

For example, if I have the following php:

  $sql="SELECT a.athleteId, a.fName, a.lName FROM Athletes a, SupportStaff s, StaffAthletes sa WHERE sa.staffId = $id AND a.athleteId = sa.athleteId"; 
  $result=mysql_query($sql);

Then:

How do I populate the drop down menu with the list of tuples retrieved from the relation?
How should the php, html and jQuery be integrated?

I have the following, but it doesn't work- It just displays a blank page:

<?php
error_reporting(E_ALL)
session_start();
//connect to database
function connect() {
  $dbh = mysql_connect ("localhost", "d", "a") or die ('I cannot connect to the database because: ' . mysql_error());
  mysql_select_db("PDS", $dbh); 
  return $dbh;
}

if(isset($_SESSION['username'])){
  $dbh = connect();
  $id = $_SESSION['id'];
  $sql="SELECT a.athleteId, a.fName, a.lName FROM Athletes a, SupportStaff s, StaffAthletes sa WHERE sa.staffId = $id AND a.athleteId = sa.athleteId"; 
  $result=mysql_query($sql); 

  $options="";   
  $i = 1;
  while ($row=mysql_fetch_array($result)) { 
    $f=$row["fName"]; 
    $l=$row["lName"]; 
    $options.="<OPTION VALUE=\"$i\">".$f.' '.$l."</OPTION>"; 
    $i++;
  }
?>

<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
   <head>
   <meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" />
   <script src = "jQuery.js"></script>
   <script>
   $(document).ready(function(){
       $("#go").click(function(e){
       if($("#selectathlete option:selected").val() == "0"){
         alert("Please Select An Athlete");
       }else{
         //set hidden textfield
         $("form#profile").submit();
       }
       });
   });
  </script>
  <title>Personal Diary System - Home Page</title>
  </head>
  <body>
  <h1>Home Page</h1>
  <p>Select An Athlete: 
  <SELECT ID ="selectathlete" NAME="athletes"> 
  <OPTION VALUE="0">Choose</OPTION>
  <?php echo($options);?>
  </SELECT>
  </p>
  <form id = "profile" name="input" action="viewathleteprofile.php" method="post">
  &l开发者_如何学Ct;input type = "hidden" id = "athleteId">
  <input type = "button" name = "go" id = "go" value = "Go">
  </form>
  </body>
</html>

I've been debugging for hours and it just doesn't work...

You should try to error_reporting(E_ALL) your page, so that you can see any and all errors your page comes across.
What's connect()? did you mean mysql_connect()?
(Kinda unrelated) You shouldn't use mysql_* functions, use MySQLi (Good) or PDO (Awesome).

when i get stuck on server 500 errors i go over to http://phpcodechecker.com/ and paste in the page. when i did that on what code you have now, it complained about a missing ; on line 2.

another tip: you can use this syntax style for slightly less complex output: $out = "text {$var} {$var2} {$array['index']}".DEFINITION_ONE

surprisingly this works for html attributes which we expect to output as "value" e.g. $options .= "{$i} {$f}

make sure your file is a .php, not .html
don't forget "<?php" at the top of page.
try to write "echo 'hello';" at the top your page to see if it prints.

this seems trivial, but as you seem to have pasted the full code, i just wanted to make sure.

Perhaps $_SESSION['username'] isn't set? You don't have a closing brace on that if statement, so if isset($_SESSION['username']) returns false, the whole page never gets displayed.