ASP.NET Simulate Postback in Windows Application - asp.net

I need to access information on a url which loads after filling its form and clicking on a button (postback). but I don't want to load page and fill the form and click that button programmatically, Is there a way to load a url with a header (or any other way ) containing those information (filled form and clicked on button) ?
Windows form or ASP.NET way solutions ...

You can use a WebClient for that. It can send a NameValueCollection of form fields and their values as a POST to an external url.
using (WebClient client = new WebClient())
{
byte[] response = client.UploadValues("http://www.post_url.nl", new NameValueCollection()
{
{ "form_input_name_1", "value_1" },
{ "form_input_name_2", "value_2" },
});
string responseString = Encoding.Default.GetString(response);
}

Related

ASP.Net Drop Down List not passing a value when updated using ajax

I have some jQuery that I'm using to open a pop-up window where a new consignor can be added to the database. The original window has a dropdownlist of all of the current consignors. When you add the new consignor in the pop-up window, that window closes and the original window then reloads the dropdownlist's data and selects the one just created.
All of that works perfectly. My issue is that when you fill out the rest of the form and submit it, it passes an empty string instead of the value of the selected item. Is this because it's an ASP.Net script? I don't know a lot about ASP.Net, but I've never had this issue with PHP. Can someone explain how I would go about refreshing the dropdownlist without refreshing the entire page and still get the list to pass it's value upon form submission?
My javascript code on the page that opens the pop-up and reloads the list is below:
function openConsignorAdd() {
var url;
url = "/admin/consignor/csAdd.aspx";
window.open(url, "WizardWindow", "width=400,height=500,resizable=yes,scrollbars=yes");
}
function loadNewAdded(fn, cs_txt_id) {
// var pagePath = window.location.pathname;
var pagePath = "/admin/getNewList.asp";
var paramList = "data=";
//Call the page method
$.ajax({
type: "POST",
url: pagePath + "?type=" + fn + "&cs_txt_id=" + cs_txt_id,
data: paramList,
success: function (data) {
//create jquery object from the response html
var $response = $(data);
//query the jq object for the values
var results = $response.filter('select#results').html();
if (fn == "consignor") {
$("select#<%=itemConsigner.ClientID%>").html(results);
} else if (fn == "cdr") {
$("select#<%=itemCDR.ClientID%>").html(results);
}
},
error: function () {
alert("Failed To Refresh!\n\nYou must manually refresh the page.");
}
});
}
My javascript code on the pop-up page to refresh the list is:
function refreshOpener(cs_txt_id) {
window.opener.loadNewAdded("consignor", cs_txt_id);
}
Those both work. And to get the value of my dropdownlist, I simply use:
if (itemConsigner.SelectedValue.ToString() != string.Empty)
{
itemCsTxtId = itemConsigner.SelectedValue.ToString();
}
with my dropdownlist being:
<asp:DropDownList ID="itemConsigner" runat="server" TabIndex="1"></asp:DropDownList>
If you need more info, just let me know. Any help is appreciated.
It seems that the issue is that since I am making the change after the page loads, the server does not see my new addition as one of the original options so ignores it completely. This is good so that people cannot just edit your forms I guess. So what I did was instead of getting the value of itemConsigner.SelectedValue, I grab the value for Request.Form["itemConsigner"] with the long ID. That way it doesn't validate that my submitted option was an original option.
Might be a silly observation but without all the code I'm not sure if this is the case. Are you just updating the original list with the id in the select options. The value needs to be populated as well for each. That could be why you are getting an empty value on after form submission.

Invoke server side method using XMLHttpRequest

how can i directly call my own server side function using XMLHttpRequest.
suppose i have one static webmethod in my aspx file then how can i call it by XMLHttpRequest. what header info i need to pass to asp.net engine and as a result asp.net engine can invoke my method and return the response back in the out going stream.
this way i need to call my server side method
<script type="text/javascript">
var request;
// A
// Here is the new function that is called when the user submits the form.
// This example uses POST.
function submitCallback() {
var inputValue = document.getElementById("SearchInput").value;
var sendStr = "name=" + inputValue;
request = new XMLHttpRequest();
// B
// Specify the POST method and send it.
request.open("POST", "Default.aspx/Getdata");
request.onreadystatechange = readyCallback;
request.setRequestHeader("Content-Type", "application/x-www-form-urlencoded");
request.setRequestHeader("IsLookup", "true");
request.send(sendStr);
}
</script>
please guide me....thanks
I believe you are probably referring to ASP.NET Page Methods when you say One static webmethod in my aspx file. ASP.NET page methods (or web services for consumption in JS) uses JSON serialization for i/p and o/p. So you need to set JSON as the content type for the request and actually send the JSON string in the body i.e.
...
var sendStr = "{name:" + inputValue + "}";
...
request.setRequestHeader("Content-Type", "application/json");
...
request.send(sendStr);
Further, I will suggest you to use jquery or ASP.NET generated proxies (by ScriptManager) instead of directly coding against XmlHttpRequest. See this article for how to use jquery for calling Page methods.
I think, the easiest way will be usage of jQuery for ajax requests: http://api.jquery.com/category/ajax/

jQuery UI autocomplete is not displaying results fetched via AJAX

I am trying to use the jQuery UI autocomplete feature in my web application. What I have set up is a page called SearchPreload.aspx. This page checks for a value (term) to come in along with another parameter. The page validates the values that are incoming, and then it pulls some data from the database and prints out a javascript array (ex: ["item1","item2"]) on the page. Code:
protected void Page_Load(object sender, EventArgs e)
{
string curVal;
string type ="";
if (Request.QueryString["term"] != null)
{
curVal = Request.QueryString["term"].ToString();
curVal = curVal.ToLower();
if (Request.QueryString["Type"] != null)
type = Request.QueryString["Type"].ToString();
SwitchType(type,curVal);
}
}
public string PreLoadStrings(List<string> PreLoadValues, string curVal)
{
StringBuilder sb = new StringBuilder();
if (PreLoadValues.Any())
{
sb.Append("[\"");
foreach (string str in PreLoadValues)
{
if (!string.IsNullOrEmpty(str))
{
if (str.ToLower().Contains(curVal))
sb.Append(str).Append("\",\"");
}
}
sb.Append("\"];");
Response.Write(sb.ToString());
return sb.ToString();
}
}
The db part is working fine and printing out the correct data on the screen of the page if I navigate to it via browser.
The jQuery ui autocomplete is written as follows:
$(".searchBox").autocomplete({
source: "SearchPreload.aspx?Type=rbChoice",
minLength: 1
});
Now if my understanding is correct, every time I type in the search box, it should act as a keypress and fire my source to limit the data correct? When I through a debug statement in SearchPreload.aspx code behind, it appears that the page is not being hit at all.
If I wrap the autocomplete function in a .keypress function, then I get into the search preload page but still I do not get any results. I just want to show the results under the search box just like the default functionality example on the jQuery website. What am I doing wrong?
autocomplete will NOT display suggestions if the JSON returned by the server is invalid. So copy the following URL (or the returned JSON data) and paste it on JSONLint. See if your JSON is valid.
http://yourwebsite.com/path/to/Searchpreload.aspx?Type=rbChoice&term=Something
PS: I do not see that you're calling the PreLoadStrings function. I hope this is normal.
A couple of things to check.
Make sure that the path to the page is correct. If you are at http://mysite.com/subfolder/PageWithAutoComplete.aspx, and your searchpreload.aspx page is in another directory such as http://mysite.com/anotherFolder/searchpreload.aspx the url that you are using as the source would be incorrect, it would need to be
source: "/anotherFolder/Searchpreload.aspx?Type=rbChoice"
One other thing that you could try is to make the method that you are calling a page method on the searchpreload.aspx page. Typically when working with javascript, I try to use page methods to handle ajax reqeusts and send back it's data. More on page methods can be found here: http://www.singingeels.com/Articles/Using_Page_Methods_in_ASPNET_AJAX.aspx
HTH.

adding dynamic message at end of flash video

I am working on a Flash training video. I would like at the end of the video for a message to pop up with a dynamic confirmation code. I have the code for the confirmation code, but am having trouble creating something either at the end of the flash video or within the aspx page to trigger this message. Any thoughts or ideas of how to solve this would be greatly appreciated.
Thank You.
Depend on the purpose of the application, you can do either one. One thing to consider is does the user has to go through the flash video to obtain the code. If so, you need to organize the flow of the application in a way that the user can't cheat their way to obtain the code.
The ideal way is to have the flash called aspx page at the end of the movie to obtain the dynamic code. This can be done using URLLoader in ActionScript 3.0 or LoadVars in ActionScript 2.0.
URLLoader example
//this is the data
var data = "This is data";
//url of your aspx code
var request:URLRequest = new URLRequest("http://www.yourdomain.com/GenerateCode.aspx");
request.contentType = "text/xml";
request.data = data;
//use POST method
request.method = URLRequestMethod.POST;
var loader:URLLoader = new URLLoader();
try
{
//execute the request
loader.load(request);
}
catch (error:ArgumentError)
{
trace("There is an ArgumentError.");
}
LoadVars example:
//create LoadVars object
var lv_in:LoadVars = new LoadVars();
var lv_out:LoadVars = new LoadVars();
//set onLoad event
lv_in.onLoad = function(success:Boolean)
{
//if success, meaning data has received response from .net page, run this code
if (success)
{
//lv_in.status is use to get the posted data from .Net page
statusMsg.text = "Thank you!" + lv_in.status;
}
//if fail, run this code
else
{
statusMsg.text = "Error!";
}
}
//this is the data
lv_out.data = "This is data";
//begin invoke aspx page
lv_out.sendAndLoad("GenerateCode.aspx", lv_in, "POST");
There another easier way but not the best practice i should say. The easier way would be to direct user to aspx page that generate dynamic code after users finish the flash movie. The negative side is, the page can be accessed although users did not finish the flash movie.

How to open new window with streamed document in ASP.NET Web Forms

I have an ASP.NET Web Forms application. I want to have a button to post back to the server that will use my fields on my form (after validation) as parameters to a server process that will generate a document and stream it back to the browser. I want the form to be updated with some status results.
What is the best way to achieve this? Right now, I've got the button click generating the document and streaming it back to the browser (it's a Word document and the dialog pops up, and the Word document can be opened successfully) but the page doesn't get updated.
I have jQuery in my solution, so using js isn't an issue if that is required.
I have a very similar process on one of my servers, and the way I've handled it is to create a temporary document on the server rather than doing a live stream. It requires a bit of housekeeping code to tidy it up, but it does mean that you can return the results of the generation and then do a client-side redirect to the generated document if successful. In my case, I'm using jQuery and AJAX to do the document generation and page update, but the same principle should also apply to a pure WebForms approach.
This was way more difficult to do than I thought. The main issue is with opening a new browser window for a Word document. The window briefly flashes up, then closes - no Word document appears. It seems to be a security issue.
If i click a button on my page, I can stream the Word doc back as the response, and the browser dialog pops up allowing me to Open/Save/Cancel, but of course, my page doesn't refresh.
My final solution to this was to use a client script on the button click to temporarily set the form's target to _blank. This forces the response to the click on the postback to go to a new browser window (which automatically closes after the download dialog is dismissed):
<asp:Button Text="Generate Doc" runat="server" ID="btnGenerateDoc"
onclick="btnGenerateDoc_Click" OnClientClick="SetupPageRefresh()" />
My SetupPageRefresh function is as follows:
function SetupPageRefresh() {
// Force the button to open a new browser window.
form1.target = '_blank';
// Immediately reset the form's target back to this page, and setup a poll
// to the server to wait until the document has been generated.
setTimeout("OnTimeout();", 1);
}
Then my OnTimeout function resets the target for the form, then starts polling a web service to wait until the server process is complete. (I have a counter in my Session that I update once the process has completed.)
function OnTimeout() {
// Reset the form's target back to this page (from _blank).
form1.target = '_self';
// Poll for a change.
Poll();
}
And the Poll function simply uses jQuery's ajax function to poll my web service:
function Poll() {
var currentCount = $("#hidCount").val();
$.ajax({
url: "/WebService1.asmx/CheckCount",
data: JSON.stringify({ currentCount: currentCount }),
success: function (data) {
var changed = data.d;
if (changed) {
// Change recorded, so refresh the page.
window.location = window.location;
}
else {
// No change - check again in 1 second.
setTimeout("Poll();", 1000);
}
}
});
}
So this does a 1 second poll to my web service waiting for the Session's counter to change from the value in the hidden field on the page. This means it doesn't matter how long the server process takes to generate the Word document (and update the database, etc.) the page won't refresh until it's done.
When the web service call comes back with true, the page is refreshed with the window.location = window.location statement.
For completeness, my Web Service looks like this:
/// <summary>
/// Summary description for WebService1
/// </summary>
[WebService(Namespace = "http://tempuri.org/")]
[WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)]
[System.ComponentModel.ToolboxItem(false)]
// To allow this Web Service to be called from script, using ASP.NET AJAX, uncomment the following line.
[System.Web.Script.Services.ScriptService]
public class WebService1 : WebService
{
[WebMethod(EnableSession=true)]
public bool CheckCount(int currentCount)
{
if (Session["Count"] == null)
Session["Count"] = 0;
var count = (int)Session["Count"];
var changed = count != currentCount;
return changed;
}
}
Hopefully that helps somebody else!

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