Here's another one for you to help me solve: I have an ASP.NET website that uses AJAX (asynchronous) calls to am .ashx handler, passing a query string parameter to get some information from the database.
Here's an example of how it works:
Client-side (Javascript) code snippet that makes the asynchronous call to the handler:
/* Capture selected value from a DropDownBox */
var dropdown = document.getElementById(DropDownID);
var selectedValue = dropdown.options[dropdown.selectedIndex].value;
/* Make the call to the handler */
var url = "MyHandler.ashx?param=" + selectedValue;
var ajaxObj = new Ajax();
ajaxObj.doRequest(url, MyCallback, args, connectionFailed);
When I load the webform (that contains this AJAX call) for the first time, it sends the right query string to the handler (I checked it using debug in Visual Studio), like param = Street Joseph Blíss. That's the right behavior I want it to have.
The thing is that when I load that webform again (and all subsequent times), that í character from "Blíss" appears in server-side as Ã-. As that's the key from the entity I'm trying to select on server-side database access script, it doesn't work as it worked on 1st webform load.
I tried encoding the query string on client-side and decoding it on server-side, using something like this:
Client-side (Javascript):
var encodedParam = encodeURIComponent(selectedValue);
/* Make the call to the handler */
var url = "MyHandler.ashx?param=" + encodedParam ;
Server-side (ASP.NET, C#):
string encodedParam = context.Request.QueryString["param"];
string value = HttpUtility.UrlDecode(encodedParam, Encoding.ASCII);
...but I had no luck with it and the problem still remains. Any help?
After some more searching, I found out how to solve with server-side code refinement. Here's the deal:
I had to alter my .ashx handler to parse the original parameter grabbed from the query string and convert it into UTF-8. Here's how it's made:
// original parameterized value with invalid characters
string paramQs = context.Request.QueryString["param"];
// correct parsed value from query string parameter
string param = Encoding.UTF8.GetString(Encoding.GetEncoding("iso8859-1").GetBytes(paramQs));
Happy coding, folks! :)
Related
I want to retrieve the file name and perform some validation on that filename. so before uploading i have to get the filename of the file selected for uploading.
Actually what i wanted is to get the filename and retrieve some fields from database based on which file is chosen , and send the data retrieved from database on the client side in some textfield. So for that before on click of upload i need to call a method in code behind which will validate all these things. I tried using AjaxControlToolkit, its not working.
Use GetFileName() method. Below example from MSDN link.
string fileName = #"C:\mydir\myfile.ext";
string path = #"C:\mydir\";
string result;
result = Path.GetFileName(fileName);
Console.WriteLine("GetFileName('{0}') returns '{1}'",
fileName, result);
result = Path.GetFileName(path);
Console.WriteLine("GetFileName('{0}') returns '{1}'",
path, result);
// This code produces output similar to the following:
//
// GetFileName('C:\mydir\myfile.ext') returns 'myfile.ext'
// GetFileName('C:\mydir\') returns ''
If you want to validate the filename on the client prior to sending it to the server you will not be able to do so with C#, you could quite easiy write a validation function in Javascript however.
You could perform server side validation of the file, but that would mean after uploading it. You could then make sure the file fulfills all your validation criterias and if it for some reason fails validation you could return the error message to the user. But that would mean a full postback of the page.
See below code example to get the file name :
var filePath = "C:\\SpiderCode\\MyFile.txt";
var fileName = System.IO.Path.GetFileName(filePath);
Client Side Code
<asp:FileUpload runat="server" ID="FileUpload" Width="100px" />
In code behind, check if user select any file, then it will simply gives you the file name in the fileName variable.
if (FileUpload.HasFile)
{
string fileName = FileUpload.FileName;
}
I have been trying to find the question to my answer but I'm unable to and finally I'm here. What I want to do is access the value passed to a webpage (GET, POST request) using asp.net. To be more clear, for example:
URL: http://www.foobar.com/SaleVoucher.aspx?sr=34
Using asp.net I want to get the sr value i.e 34.
I'm from the background of C# and new to ASP.NET and don't know much about ASP.NET.
Thanx.
Can you refer to this QueryString
Here he says how to access the query string using:
Request.Url.Query
That is not called a Header, but the Query String.
the object document.location.search will contain that and the javascript to get any query string value based on the key would be something like:
function getParameterByName(name) {
name = name.replace(/[\[]/, "\\\[").replace(/[\]]/, "\\\]");
var regex = new RegExp("[\\?&]" + name + "=([^&#]*)"),
results = regex.exec(location.search);
return results == null ? "" : decodeURIComponent(results[1].replace(/\+/g, " "));
}
code from other question: https://stackoverflow.com/a/901144/28004
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.
I don't know much about Flash but we are working on a site that has a flash form and when the users pick an option, like selecting a value from a drop down list, we need the value to be passed to asp.net server-side code. What's the easiest way to do this?
Flash can invoke server side service. So use GET or POST to pass data
You could explore these options:
1) Communicate between the SWF and the containing page through JavaScript
2) Communicate via asp.net webservices from the SWF directly to the webservice.
3) Not sure but could probably do a POST to a processing aspx page?
HTH
I think a good option is to use the XML class so consider this:
var xmlRequest = new XML();
xmlRequest.onLoad = parseXMLResponse;
xmlRequest.load("http://yourpathtoyourserver/file.aspx?listselectedvalue=something");
function parseXMLRequest(loaded)
{
trace("hi");
}
You can also have the page give you data back this way so it's not just one way communication.
Assuming you are using Action Script 2.
Read the important notes at the bottom of each codes pertain to sending and retrieving data from flash to .net page. Explanation of the code is in the comment inside the code.
Flash Part (Action Script 2)
//function to send collected form data to asp.net page
//use other control/button to call this function
//important: in order for the 'onLoad' event to work correctly, this function has to be 'Void'
function sendForm():Void
{
//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 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 for filling up the form!" + lv_in.status;
}
//if fail, run this code
else
{
statusMsg.text = "The form you are trying to fill up has an error!";
}
}
//this is the collected data from the form
lv_out.userName = txtUserName.text;
lv_out.userAddress = txtUserAddress.text;
lv_out.userBirthday = txtUserBirthday.text;
//begin invoke .net page
lv_out.sendAndLoad("ProcessDataForm.aspx", lv_in, "POST");
}
Important note:
The function that contain onLoad event, in this case sendForm function, has to be Void function, meaning it's not returning value. If this function return value, what happen is the function will be executed all the way without waiting for the returned data from .net page, thus the onLoad event will not be set properly.
.Net Part
public void ProcessData
{
//process the data here
Response.Write("status=processed&");
}
Important note:
To send data/message back to flash, you can use Response.Write. However, if you want Action Script to parse the posted message/data from .Net page keep in mind you have to include & symbol at the end of the message. When parsing data/message, Action Script will stop at & symbol, thus leave the rest of the message alone and only get the message under sent variable.
We have to make an ASP.NET MVC or ASP.NET application for basic ajax navigation in Customer.html of Notrhwind.mdb.
We have this 3 things:
A pure HTML/JavaScript form having HTML input text tags, one for each field of Customers table.
We have also 2 navigation buttons: NextRecord and PrevRecord having at OnClick() event : clientGetRecord(NextOrPrev)
A javascript ajax clientGetRecord function, something like this:
function clientGetRecord(NextOrPrev) {
var oXMLHTTP = new ActiveXObject("Microsoft.XMLHTTP");
var sURL = "ServerGetRecord.aspx?ID=" + NextOrPrev;
oXMLHTTP.open( "POST", sURL, FALSE );
oXMLHTTP.send();
var sResult=oXMLHTTP.responseText;
var aRecord = sResult.split(";");
document.getElementById('CustomerID').value = aRecord[0];
document.getElementById('CompanyName').value = aRecord[1];
document.getElementById('ContactName').value = aRecord[2];
document.getElementById('Adress').value = aRecord[3];
//... and so on ...
};
We must have something like a ServerGetRecord controler function which returns to the clientGetRecord function, a simple string containing the current record fields values separated by comma and using classic ADO database handling.
The question is : How to program and invoke the ServerGetRecord function? Can i have a VB code example of ServerGetRecord function (or ASPX, or ASHX, or something else?..) ?
Don't have any VB smaples for you, but you can create a controller (asp.net mvc) that returns a JsonResult. You get your data from the DB and build the JsonResult object to return.
Then on your client use jQuery to call the controller and get the results as json format.
This post can help you get started: Link
Hope this helps