ASP.NET pass a javascript value in server side_问答_开发者

ASP.NET pass a javascript value in server side

开发者 https://www.devze.com 2023-01-14 18:48 出处：网络

Hi how can I开发者_如何学Go pass a client side (JS) value in server side (C#)? e.g. I have a generated table (after uploading images) and it containsimages and I want to select the image and throw t

相关专题：asp.net

Hi how can I开发者_如何学Go pass a client side (JS) value in server side (C#)?

e.g.

I have a generated table (after uploading images) and it contains images and I want to select the image and throw the ID back in server side.

The uploade I used was JQuery Uploadify and I have a "onComplete" function

(simple code)
'onComplete': function (event, queueID, fileObj, response, data) {
    $('#imgs').append('<img id="' + queueID + '" src="' + response + '" alt="' + response + '" />');

How can I do this?

To send a value from javascript to the server you have a couple of options:

Use AJAX if you want to stay on the current page
Redirect to a server side script and pass the value in the querystring

Let's consider the first case:

Assuming you have a web method capable of receiving the value on the server:

<%@ Page Title="Home Page" Language="C#" AutoEventWireup="true" %>
<script type="text/C#" runat="server">
    // Server side script in the code behind that will receive
    // the value: The method needs to be static
    // and decorated with the WebMethod attribute
    [System.Web.Services.WebMethod]
    public static string Foo(string id)
    {
        return "ok";
    }
</script>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en">
<head id="Head1" runat="server">
    <title></title>
    <link href="~/Styles/Site.css" rel="stylesheet" type="text/css" />
    <script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.4/jquery.min.js"></script>
    <script type="text/javascript">
        $(function () {
            // Send an AJAX request to the server
            $.ajax({
                url: '/default.aspx/foo',
                type: 'POST',
                contentType: 'application/json; charset=utf-8',
                // Pass the value as JSON string
                // You might need to include json2.js for the JSON.stringify
                // method: http://www.json.org/json2.js
                data: JSON.stringify({ id: 'someId123' }),
                success: function (result) {
                    // The result is also JSON
                    alert(result.d);
                }
            });
        });
    </script>
</head>
<body>
    <form id="Form1" runat="server">

    </form>
</body>
</html>

are you using Asp.net Forms? If so, you do understand the concept of Page Lifecycle and how it affects the state of the page?

I would suggest going javascript all the way in this one, please see jQuery + AJAX.