Do php query with ajax_问答_开发者_运维开发者技术经验分享

I'd like to do a sql query with ajax so I don't need to reload the page / load a new page.

So basicly I need to call a php page with ajax. And it would be great if there could be a way to reload a count of amount of rows in a table too.

Edit: to make it more clear, it should be able to do something along the lines of开发者_JS百科 when you click the Like button on Facebook.

Thanks

<html>
<head>
<script type="text/javascript">
function loadXMLDoc()
{
var xmlhttp;
if (window.XMLHttpRequest)
{// code for IE7+, Firefox, Chrome, Opera, Safari
 xmlhttp=new XMLHttpRequest();
}
else
{// code for IE6, IE5
  xmlhttp=new ActiveXObject("Microsoft.XMLHTTP");
}
     xmlhttp.onreadystatechange=function()
{
    if (xmlhttp.readyState==4 && xmlhttp.status==200)
    {
        document.getElementById("your_div").innerHTML=xmlhttp.responseText;
    }
  }
xmlhttp.open("GET","ajax_file.php",true);
xmlhttp.send();
}
</script>
</head>
<body>

<div id="myDiv">here are your contents</div>
<button type="button" onclick="loadXMLDoc()">Change Content</button>

</body>
</html>

You don't want to query using ajax, you want to get new data using ajax, which is a fundamental difference.

You should just, using ajax, request a php page with perhaps some parameters, which in turn executes the query and returns the data in a format you can handle (most likely: json).

If you allow queries to be executed using ajax, how are you going to prevent a malicious user from sending drop table users, instead of select * from news where id = 123?

You won't do a sql query with ajax, what you need to do is call an external php page (one where your query is) in the background using ajax. Here is a link that explains how to do it with jquery: http://api.jquery.com/jQuery.ajax/

"Facebook Like" button in Agile Toolkit (PHP UI Library):

$likes = get_like_count();

$view = $this->add('View');
$button = $view->add('Button')->setLabel('Like');
$view->add('Text')->set($likes);

if($button->isClicked()){
    increate_like_count();
    $view->js()->reload()->execute();
}

p.s. no additional JS or HTML code needed.

function onClick(){
     $.post(
        "path/to/file", //Ajax file ajax_file.php        
        { value : value ,insiId : insiId  },  // parameters if you want send        
        //function that is called when server returns a value.
        function(data){
            if(data){
                $("#row_"+data.id).show();     //display div rows               
            }
        },"json"   
    );
}
<div id="myDiv">here are your contents</div>
<button type="button" onclick="onClick()">Change Content</button>

Here the ajax code that you can call to the server side php file and get the out put and do what you want

You are wrong, who says that he is submitting the whole query who is telling that he is not filtering? U can do all this easy with the jquery load function, you load a php file like that $('#BOX').load('urfile.php?param=...');.

Have fun, i hope that was a little helpful for you, sry bcs of my bad english.

Possible solution: Ajax calls PHP scripts which make the query and return the new number

$.ajax({
    async:true,
    type:GET,
    url:'<PHP_FILE>',
    cache:false,
    data:'<GET_PARAMETERS_SENT_TO_PHP_FILE>',
    dataType:'json',
    success: function(data){
        $('<#HTML_TARGET>').html(data);
    },      
    error: function(jqXHR, textStatus, errorThrown){
        $('<#HTML_TARGET>').html('<div class="ajax_error">'+errorThrown+'</div>');
    }
});

Where

<PHP_FILE> is your php script which output must be encoded according to dataType. The available types (and the result passed as the first argument to your success callback) are: "xml", "html", "script", "json", "jsonp", "text".
<GET_PARAMETER_SENT_TO_PHP> is a comma separate list of value sent via GET (es. 'mode=ajax&mykey=myval')
<#HTML_TARGET> is the jquery selector

See jquery.ajax for more details.

For example:

<p>Votes:<span id="count_votes"></span></p> 
<script type="text/javascript">
    $.ajax({
        async:true,
        type:GET,
        url:'votes.php',
        cache:false,
        dataType:'text',
        data:'id=4'
        success: function(data){
            $('#count_votes').html(data);
        },      
        error: function(jqXHR, textStatus, errorThrown){
            $('#count_votes').html(errorThrown);
        }
    });
</script>

If your looking for something like the facebook like btn. Then your PHP code should look something like this -

<?php

$topic_no = $_POST['topic'];

$topic_likes = update_Like_count($topic_no);

echo $topic_likes;

function update_Like_count($topic)
{
    //update database by incrementing the likes by one and get new value

    return $count;
}
?>

and the javascript/jquery ajax should be something like so -

<script>

      $('#like-btn').click( function () {

             $.post(

            "like.php",

            { topic : value },

            function(data)
            {
                if(data)
                {
                    $("#like-btn span").append(data);     //or append it to wherever you'd like to show it              
                }
                else
                {
                    echo "error";
                }
            },
            "json"
        );
        });


</script>

Here is an example which uses a favorite jQuery plugin of mine, jQuery.tmpl(), and also the jQuery .text() function.

HTML and Javascript Code:

<!DOCTYPE html>
<html>
<head>
  <script src="http://code.jquery.com/jquery-latest.min.js"></script>
  <script src="http://ajax.microsoft.com/ajax/jquery.templates/beta1/jquery.tmpl.min.js"></script>
</head>
<body>

<script id="UserTemplate" type="text/x-jquery-tmpl"> 
    <li><b>Username: ${name}</b> Group ID: (${group_id})</li>
</script>


<button id="facebookBtn">Facebook Button</button>
<div id="UserCount"></div>
<ul id="userList"></ul>

<script>
function getData(group_id) {
    $.ajax({
        dataType: "json",
        url: "test.php?group_id=" + group_id,
        success: function( data ) {

            var users = data.users;

            /* Remove current set of movie template items */
            $( "#userList" ).empty();

            /* Render the template with the movies data and insert
               the rendered HTML under the "movieList" element */
            $( "#UserTemplate" ).tmpl( users )
                .appendTo( "#userList" );

            $( "#UserCount" ).text('Number of users: '+ data.count);

        }
    });
}

$( "#facebookBtn" ).click( function() {
    getData("1");
});

</script>

</body>
</html>

PHP Code

<?php
//Perform a query using the data passed via ajax
$group_id = $_GET['group_id'];
$user_array = array(
  array('name'=>'John','group_id'=>'1',),
  array('name'=>'Bob','group_id'=>'1',),
  array('name'=>'Dan','group_id'=>'1',),
);
$user_count = count($user_array);
echo json_encode(array('count'=>$user_count,'users'=>$user_array));

HTML:

//result div will display result
<div id="result"></div>
<input type="button" onclick="getcount();" value="Get Count"/>

JS:

//will make an ajax call to ustom_ajax.php
function getcount()
{

    $.ajax({
        type:"get",
        url : "custom_ajax.php",
        beforeSend: function() {        
                // add the spinner 

                $('<div></div>')
                  .attr('class', 'spinner')
                  .hide()
                  .appendTo("#result")
                  .fadeTo('slow', 0.6);
              },
        success : function (data) {             
        $("#result").html(data);
        },
        complete: function() {        
                // remove the spinner 
                $('.spinner').fadeOut('slow', function() {
                  $(this).remove();
                });
        }
    });
}

custom_ajax.php:

 //will perform server side function
//make a connection and then query 
$query_txt = "SELECT count(*) FROM table "; 
$result= mysql_query($query_txt) or die(mysql_error()); 
$total=mysql_num_rows($result) ;
$html= "Total result is $total";    
echo $html; exit();