I have a 3 step chained-select sequence, game -> battle -> winning side
, which pulls all data from a MySQL database.
After some wandering on the internet, I found a compact jQuery script that performs wonderfully. However, I am at a loss as to how to allow for existing data: <option selected="selected"></option>
using this script.
chained select javascript:
<script>
var ajax = new Array();
function getScenNumList(sel)
{
var game = sel.options[sel.selectedIndex].value;
document.getElementById('scenarioNumber').options.length = 0; // Empty scenario number select box
if(game.length>0){
var index = ajax.length;
ajax[index] = new sack();
ajax[index].requestFile = 'js/getPlayData.php?gameName='+game; // Specifying which file to get
ajax[index].onCompletion = function(){ createScenarioNumbers(index) }; // Specify function that will be executed after file has been found
ajax[index].runAJAX(); // Execute AJAX function
}
}
function createScenarioNumbers(index)
{
var obj = document.getElementById('scenarioNumber');
eval(ajax[index].response); // Executing the response from Aja开发者_Go百科x as Javascript code
}
function getNations(sel)
{
var scenNum = sel.options[sel.selectedIndex].value;
document.getElementById('victor').options.length = 0; // Empty nation select box
if(scenNum.length>0){
var index = ajax.length;
ajax[index] = new sack();
ajax[index].requestFile = 'js/getPlayData.php?scenID='+scenNum; // Specifying which file to get
ajax[index].onCompletion = function(){ createNations(index) }; // Specify function that will be executed after file has been found
ajax[index].runAJAX(); // Execute AJAX function
}
}
function createNations(index)
{
var obj = document.getElementById('victor');
eval(ajax[index].response); // Executing the response from Ajax as Javascript code
}
</script>
excerpt from the PHP database retrieval script (getPlayData.php
):
$gameName = mysql_real_escape_string($_GET['gameName']);
$q = "SELECT a, b, c FROM table WHERE game='$gameName' ORDER BY num ASC";
$r = mysql_query($q);
echo "obj.options[obj.options.length] = new Option('#','');\n";
while ($row = mysql_fetch_row($r)) {
$string = mysql_real_escape_string(($row[0].' - '.$row[1])); // needed so quotes ' " don't break the javascript
echo "obj.options[obj.options.length] = new Option('$string','$row[2]');\n";
}
echoing the obj.options
is the stock method this script was using. It seems ugly to me, but I don't know any javascript so I didn't want to fiddle with it.
The HTML is simple enough, just a table with a few empty <select>
objects with IDs matching those in the javascript and onchange="getXXX(this)"
calls.
My question is this: Everything works great for new records, but I'm at a loss as to how I can alter this to support marking one option from each select as selected, assuming I have that data in hand (ex: a user is editing an existing record) ?
Many thanks!
You can see this tutorial for creating an option that is selected as default. http://www.javascriptkit.com/javatutors/selectcontent.shtml One parameter in the option constructor dictate that whether the option is selected or not.
In the PHP file you will edit as follow:
$gameName = mysql_real_escape_string($_GET['gameName']);
$q = "SELECT a, b, c FROM table WHERE game='$gameName' ORDER BY num ASC";
$r = mysql_query($q);
echo "obj.options[obj.options.length] = new Option('#','');\n";
while ($row = mysql_fetch_row($r)) {
$string = mysql_real_escape_string(($row[0].' - '.$row[1])); // needed so quotes ' " don't break the javascript
if ($string ......)
echo "obj.options[obj.options.length] = new Option('$string','$row[2]', false, true);\n";
else
......
}
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