views:

900

answers:

3

I'm using the W3 Schools example: http://www.w3schools.com/PHP/php_ajax_database.asp to display a table of database data given the choice from a single select box. How can I modify this to include another select box, say for example I wanted records matching a name and an age?

A: 

Change

<select name="users" onchange="showUser()" id="name_select">

ADD age drop down from 1 to 100

<select name="age" onchange="showUser()" id="age_select">
  <option value="1">1</option>
  <option value="2">2</option>
                   |
  <option value="100">100</option>
</select>

Change

function showUser(str)
{
xmlhttp=GetXmlHttpObject();
if (xmlhttp==null)
  {
  alert ("Browser does not support HTTP Request");
  return;
  }
name= document.getElementByID('name_select').value
age= document.getElementByID('age_select').value
var url="getuser.php";
url=url+"?q="+str+"&age="+age;
url=url+"&sid="+Math.random();
xmlhttp.onreadystatechange=stateChanged;
xmlhttp.open("GET",url,true);
xmlhttp.send(null);
}

change in php

$age=$_GET["age"];
$sql="SELECT * FROM user WHERE id = '".$q."' and age=".$age;
Salil
Won't this be a problem if they *don't* select an age?
dclowd9901
I'm having problems, now nothing happens if I change the selections
Robert
@Robert sorry dear your showUser(str) now should be showUser()
Salil
Works great now, thanks!
Robert
A: 

You can try this (the following piece of code is not tested, but it should work)

The HTML Page

<html>
<head>
<script type="text/javascript" src="selectuser.js"></script>
</head>
<body>

<form>
Select a User:
<select name="users" id="users">
<option value="1">Peter Griffin</option>
<option value="2">Lois Griffin</option>
<option value="3">Glenn Quagmire</option>
<option value="4">Joseph Swanson</option>
</select>

Select an age:
<select name="age" id="age">
<option value="39">39</option>
<option value="40">40</option>
<option value="41">41</option>
<option value="42">42</option>
</select>

<input type='button' value='Refresh Data' onclick="showUser(document.getElementById('users').value,document.getElementById('age').value)">
</form>
<br />
<div id="txtHint"><b>Person info will be listed here.</b></div>

</body>
</html>

The Java script code as:

var xmlhttp;

function showUser(str,age)
{
xmlhttp=GetXmlHttpObject();
if (xmlhttp==null)
  {
  alert ("Browser does not support HTTP Request");
  return;
  }
var url="getuser.php";
url=url+"?q="+str+"&a="+age;
url=url+"&sid="+Math.random();
xmlhttp.onreadystatechange=stateChanged;
xmlhttp.open("GET",url,true);
xmlhttp.send(null);
}

function stateChanged()
{
if (xmlhttp.readyState==4)
{
document.getElementById("txtHint").innerHTML=xmlhttp.responseText;
}
}

function GetXmlHttpObject()
{
if (window.XMLHttpRequest)
  {
  // code for IE7+, Firefox, Chrome, Opera, Safari
  return new XMLHttpRequest();
  }
if (window.ActiveXObject)
  {
  // code for IE6, IE5
  return new ActiveXObject("Microsoft.XMLHTTP");
  }
return null;
}

The PHP Page as

<?php
$q=$_GET["q"];
$a=$_GET["a"];

$con = mysql_connect('localhost', 'peter', 'abc123');
if (!$con)
  {
  die('Could not connect: ' . mysql_error());
  }

mysql_select_db("ajax_demo", $con);

$sql="SELECT * FROM user WHERE id = '".$q."' and age='".$a."'";

$result = mysql_query($sql);

echo "<table border='1'>
<tr>
<th>Firstname</th>
<th>Lastname</th>
<th>Age</th>
<th>Hometown</th>
<th>Job</th>
</tr>";

while($row = mysql_fetch_array($result))
  {
  echo "<tr>";
  echo "<td>" . $row['FirstName'] . "</td>";
  echo "<td>" . $row['LastName'] . "</td>";
  echo "<td>" . $row['Age'] . "</td>";
  echo "<td>" . $row['Hometown'] . "</td>";
  echo "<td>" . $row['Job'] . "</td>";
  echo "</tr>";
  }
echo "</table>";

mysql_close($con);
?>



Gaurav Srivastava
Is it necessary to have a button to refresh the data?
Robert
no...it is not at all necessary to add the refresh button. You can add the this: showUser(document.getElementById('users').value,document.getElementById('age').value) to the onchange event of the Select HTML field (name or age list)
Gaurav Srivastava
A: 
Rilana