jquery autocomplete source as a url that takes in query strings - c#

I am trying to use the jQuery Autocomplete UI widget on a text box and I am having no luck getting the source to work. I have a database full of names that I want the autocomplete to work against, so I created a page called searchpreload.aspx and it looks for a variable in the url and queries the db based on the querystring vraiable.
When I type in the search box, I am using the keyup function so I can capture what the value is that needs to be sent over. Then I do my string gathering from the db:
if (Request.QueryString["val"] != null)
{
curVal = Request.QueryString["val"].ToString();
curVal = curVal.ToLower();
if (Request.QueryString["Type"] != null)
type = Request.QueryString["Type"].ToString();
SwitchType(type,curVal);
}
It queries the database correctly and then it takes the strings and puts them in a list and prints them out to the page:
private void PreLoadStrings(List<string> PreLoadValues, string curVal)
{
StringBuilder sb = new StringBuilder();
if (PreLoadValues.Any())
{
foreach (string str in PreLoadValues)
{
if (!string.IsNullOrEmpty(str))
{
if (str.ToLower().Contains(curVal))
sb.Append(str).Append("\n");
}
}
Response.Write(sb.ToString());
}
}
This works fine, if I navigate to this page I get a listing of all of the data that I need, however I can not get it to show up in the autocomplete box. When I debug the code, the source of the autocomplete is calling this page correctly each time and getting the correct data, it just is not displaying anything. Am I doing something wrong?
JQuery Code:
<script type="text/javascript">
$(document).ready(function () {
$(".searchBox").focus();
var checked = 'rbCNumber';
$("input:radio").change(function (eventObject) {
checked = $(this).val();
});
$(".searchBox").keyup(function () {
var searchValue = $(".searchBox").val();
//alert("Searchpreload.aspx?val=" + searchValue + "&Type=" + checked);
$(".searchBox").autocomplete({
source:"Searchpreload.aspx?val=" + searchValue + "&Type=" + checked,
minLength: 2
});
});
});
</script>
Also, should I be doing this a different way to make it faster?

You arent displaying the results into anything - source will return a data item that you can then use to populate something else on the page. Look at autocomplete's select and focus methods.
here is an example of how i have done it:
field.autocomplete({
minLength: 1,
source: "whatever",
focus: function (event, ui) {
field.val(ui.item.Id);
return false;
},
search: function (event, ui) {
addBtn.hide();
},
select: function (event, ui) {
setup(ui);
return false;
}
})
.data("autocomplete")._renderItem = function (ul, item) {
return $("<li></li>")
.data("item.autocomplete", item)
.append("<a>" + item.Id+ ", " + item.Name + "</a>")
.appendTo(ul);
};
The .data part is the part you are missing. Once the data comes back from the autocomplete you arent doing anything with it.
The source does not need to include the term the user entered into the search box. Jquery will automatically append the term onto the query string for you. If you watch the request get generated in firebug, you will see the term query hanging off the end of the url.

Related

How to resolve a not working cascading drop down

I have a cascading dropdown like for eg first dropdown shows the list of countries and based on the selection of countries the next dropdown gets populated. The problem is that in development environment it's working fine but when deployed in a server the first dropdown gets populated correctly as it's elements come from resource file and after selection of first drop down I get an error.
JS :
<script>
$(document).ready(function () {
$("#Site").change(function () {
var SelectedVal = $(this).val();
$("#Model").html('');
$("#Model").append($("<option></option>").attr("value", '')
.text(' '));
if (SelectedVal != '') {
$.get("/Home/GetModelList", { Sid: $("#Site").val() }, function (data) {
$("#Model").empty();
$("#Model").html('');
$("#Model").append($("<option></option>").attr("value", '')
.text(' '));
if (data.modelAlert != null) {
alert(data.projectAlert);
}
$.each(data.models, function (index, item) {
$("#Model").append($('<option></option>').text(item));
});
});
}
})
});
</script>
Controller :
public JsonResult GetModelList()
{
List<string> models = db.GetModels();
string modelAlert = alert.GetAlert();
var result = new { modelAlert, models };
return Json(result, JsonRequestBehavior.AllowGet);
}
The error message that I get is
Failed to load resource: the server responded with a status of 404 (Not Found) Home/GetModelList?Sid=Ind:1
I checked for similar problems like this and it was all about the JS path or the controller path but I've already given the absolute path. Can someone let me know where am I going wrong, let me know if any additional data is needed.
Thanks
$.get("/Home/GetModelList", { Sid: $("#Site").val() }, function (data) {
The above line was causing the routing problem, usually when we call a controller action from js in this way there tends to be a routing problem due to the folder structure reference. In order to avoid this routing problem and to be more clear we can also call controller action from js like below
$.get('#Url.Action("MethodName", "ControllerName")', function (data) {
This resolved my issue.

Dropdown not binding in IE 8

I am binding dropdown list using jquery and asp.net callbacks.
this is working in IE-9,11 and other browsers also but It is not working in IE-8.
and It is not showing any error also.
I am using bellow javascript function for binding dropdown
function ClientCallback(result, context) {
if (!$('#ddltest')) {
return;
}
$('#ddltest').length = 0;
if (!result) {
return;
}
$(result).find('Table1').each(function () {
var OptionValue = $(this).find('OptionText').text();
var OptionText = $(this).find('OptionText').text();
var option = $("<option>" + OptionText + "</option>");
option.attr("value", OptionValue);
$('#ddltest').append(option);
});
}
from code behind method I am returning dataset in the form of xml like return ds.GetXml();

Saving values of html selects and re-select them on postback

I have five dropdownlists in form of html selects. The first binds at page load using jQuery, and the rest bind when the previous dropdown has been selected. I also have five hidden fields for each dropdown which stores the selected values.
My problem is that when I do a post back, i.e. click the "Search" button, I have to re-populate the dropdowns and select the correct values again by using the ID's in the hidden fields. So far, I've come up with no good way to do this.
In the .aspx page:
<select name="boxFunktionsnedsattning" id="boxFunktionsnedsattning" multiple="multiple </select>
<asp:TextBox ID="HiddenBoxFunktionsnedsattning" runat="server" />
<script type="text/javascript">
function boxFunktionsnedsattningPopulate() {
$.ajax({
type: "POST",
url: "Sok.aspx/getFunktionsnedsattningar",
data: {},
contentType: "application/json; charset=utf-8",
dataType: "json",
success: LoadBoxFunktionsnedsattning,
failure: function (response) {
alert(response);
}
});
}
//============================================================================================================
function LoadBoxFunktionsnedsattning(response) {
var result = response.d;
var options = $("#boxFunktionsnedsattning");
options.text(''); // clear the box content before reloading
if ($('#boxFunktionsnedsattning').val != '') {
options.removeAttr("disabled");
options.multipleSelect("enable");
}
else {
options.attr("disabled", true);
options.multipleSelect("disable");
}
$.each(result, function () {
options.append($("<option />").val(this.id).text(this.name));
});
UpdateBoxEnabledState();
options.multipleSelect("refresh");
}
</script>
Backend code:
[WebMethod]
[ScriptMethod(ResponseFormat = ResponseFormat.Json)]
public static Funktionsnedsattning[] getFunktionsnedsattningar()
{
GetDataService.IgetDataClient gdc = new IgetDataClient();
return gdc.getFunktionsnedsattningAll();
}
I should add that I'm a beginner when it comes to jQuery, so there is probably something I've overlooked.
IF your using webforms use an onclick function to post back to the server instead of a submit. I think this is the functionality you want because the variables in the inputs of the form will keep its value. Is the search button returning results on the same page or a different one because it will determine the ease in which you can keep varibles during a post back. Good luck!
Got it working with the following solution:
function fillFunktionsnedsattning() {
//stores the value of selected items
var $fn = $('#<%=HiddenBoxFunktionsnedsattning.ClientID%>');
//creates an array of the values in the hidden field
var fnSplit = $fn.val().split(",");
//val() accepts an array which it uses to select items in the list (go figure)
$("#boxFunktionsnedsattning").val(fnSplit);
$("#boxFunktionsnedsattning").multipleSelect("refresh");
//function that triggers the binding of the next dropdown
boxFunktionsnedsattningOnChange();
}
For it to work, this function needs to be called in the function that populates the dropdown. Each dropdown needs it's own fillFunction to be called in the same place, like this, for an example:
function LoadBoxFunktionsnedsattning(response) {
var result = response.d;
var options = $("#boxFunktionsnedsattning");
options.text(''); // clear the box content before reloading
if ($('#boxFunktionsnedsattning').val != '') {
options.removeAttr("disabled");
options.multipleSelect("enable");
}
else {
options.attr("disabled", true);
options.multipleSelect("disable");
}
$.each(result, function () {
options.append($("<option />").val(this.id).text(this.name));
});
fillFunktionsnedsattning();
UpdateBoxEnabledState();
options.multipleSelect("refresh");
It's probably possible to simplify this, but this works for me.

Problem on how to update the DOM but do a check on the data with the code-behind

This is with ASP.NET Web Forms .NET 2.0 -
I have a situation that I am not sure how to fulfill all the requirements. I need to update an img source on the page if selections are made from a drop down on the same page.
Basically, the drop downs are 'options' for the item. If a selection is made (i.e. color: red) then I would update the img for the product to something like (productID_red.jpeg) IF one exists.
The problem is I don't want to do post backs and refresh the page every time a selection is made - especially if I do a check to see if the image exists before I swap out the img src for that product and the file doesn't exist so I just refreshed the entire page for nothing.
QUESTION:
So I have easily thrown some javascript together that formulates a string of the image file name based on the options selected. My question is, what options do I have to do the following:
submit the constructed image name (i.e. productID_red_large.jpg) to some where that will verify the file exists either in C# or if it is even possible in the javascript. I also have to check for different possible file types (i.e. .png, .jpg...etc.).
not do a post back and refresh the entire page
Any suggestions?
submit the constructed image name
(i.e. productID_red_large.jpg) to some
where that will verify the file exists
either in C# or if it is even possible
in the javascript. I also have to
check for different possible file
types (i.e. .png, .jpg...etc.).
not do a post back and refresh the
entire page
If you wish to not post back to the page you will want to look at $.ajax() or $.post() (which is just short hand for $.ajax() with some default options)
To handle that request you could use a Generic Http Handler.
A simple outline could work like the following:
jQuery example for the post:
$("someButton").click(function () {
//Get the image name
var imageToCheck = $("#imgFileName").val();
//construct the data to send to the handler
var dataToSend = {
fileName: imageToCheck
};
$.post("/somePath/ValidateImage.ashx", dataToSend, function (data) {
if (data === "valid") {
//Do something
} else {
//Handle error
}
}, "html");
})
Then on your asp.net side you would create an http handler that will validate that request.
public class Handler1 : IHttpHandler
{
public void ProcessRequest(HttpContext context)
{
var fileName = context.Request["fileName"];
var fullPath = Path.Combine("SomeLocalPath", fileName);
//Do something to validate the file
if (File.Exists(fullPath))
{
context.Response.Write("valid");
}
else
{
context.Response.Write("invalid");
}
}
public bool IsReusable
{
get
{
return false;
}
}
}
Hope this helps, if I missed the mark at all on this let me know and I can revise.
We have an app of the same type, webforms .net 2, we do something similar with the following setup:
Using jQuery you can call a method in the page behind of the current page, for example, the following will trigger the AJAX call when the select box called selectBoxName changes, so your code work out the image name here and send it to the server.
$(document).ready(function () {
$('#selectBoxName').change(function (event) {
var image_name = 'calculated image name';
$.ajax({
type: "POST",
url: 'SomePage.aspx/CheckImageName',
data: "{'imageName': '" + image_name + "'}",
contentType: "application/json; charset=utf-8",
dataType: "json",
success: function (msg) {
alert(msg);
},
error: function (a, b, c) {
alert("The image could not be loaded.");
}
});
});
});
Where SomePage.aspx is the current page name, and image_name is filled with the name you have already worked out. You could replace the img src in the success and error messages, again using jQuery.
The code behind for that page would then have a method like the following, were you could just reutrn true/fase or the correct image path as a string if needed. You can even return more complex types/objects and it will automatically send back the proper JSON resposne.
[System.Web.Services.WebMethod(true)]
[System.Web.Script.Services.ScriptMethod(ResponseFormat = System.Web.Script.Services.ResponseFormat.Json)]
public static bool CheckImageName(string imageName)
{
/*
* Do some logic to check the file
if (file exists)
return true;
return false;
*/
}
As it is .net 2 app, you may need to install the AJAX Extensions:
http://www.microsoft.com/downloads/en/details.aspx?FamilyID=ca9d90fa-e8c9-42e3-aa19-08e2c027f5d6&displaylang=en
Could you not use a normal ajax call to the physical path of the image and check if it returns a 404?
Like this:
http://stackoverflow.com/questions/333634/http-head-request-in-javascript-ajax
<script type="text/javascript">
function UrlExists(url) {
var http = new XMLHttpRequest();
http.open('HEAD', url, false);
http.send();
return http.status != 404;
}
function ConstructImage() {
var e = document.getElementById("opt");
var url = '[yourpath]/' + e.value + '.jpg';
if (!UrlExists(url)) {
alert('doesnt exists');
//do stuff if doesnt exist
} else {
alert('exists');
//change img if it does
}
}
</script>
<select id="opt" onchange="ConstructImage()">
<option value="red">Red</option>
<option value="blue">Blue</option>
<option value="green">Green</option>
</select>

Save state of Widgets in ASP.NET MVC using jQuery and Json

I am using ASP.NET MVC in C#
I have a page where the user can move different Widgets around the page, and I now need a method to save the state of the widgets. I am using jQuery in the HTML page, and the jQuery posts the new page layout using JSON. I am unsure how to read the JSON in the controller.
The code I'm using is based on this example here - http://webdeveloperplus.com/jquery/saving-state-for-collapsible-drag-drop-panels/, but the code for saving the result is in PHP.
jQUERY
<script type="text/javascript" >
$(function () {
$('.dragbox')
.each(function () {
$(this).hover(function () {
$(this).find('h2').addClass('collapse');
}, function () {
$(this).find('h2').removeClass('collapse');
})
.find('h2').hover(function () {
$(this).find('.configure').css('visibility', 'visible');
}, function () {
$(this).find('.configure').css('visibility', 'hidden');
})
.click(function () {
$(this).siblings('.dragbox-content').toggle();
//Save state on change of collapse state of panel
updateWidgetData();
})
.end()
.find('.configure').css('visibility', 'hidden');
});
$('.column').sortable({
connectWith: '.column',
handle: 'h2',
cursor: 'move',
placeholder: 'placeholder',
forcePlaceholderSize: true,
opacity: 0.4,
start: function (event, ui) {
//Firefox, Safari/Chrome fire click event after drag is complete, fix for that
if ($.browser.mozilla || $.browser.safari)
$(ui.item).find('.dragbox-content').toggle();
},
stop: function (event, ui) {
ui.item.css({ 'top': '0', 'left': '0' }); //Opera fix
if (!$.browser.mozilla && !$.browser.safari)
updateWidgetData();
}
})
.disableSelection();
});
function updateWidgetData() {
var items = [];
$('.column').each(function () {
var columnId = $(this).attr('id');
$('.dragbox', this).each(function (i) {
var collapsed = 0;
if ($(this).find('.dragbox-content').css('display') == "none")
collapsed = 1;
//Create Item object for current panel
var item = {
id: $(this).attr('id'),
collapsed: collapsed,
order: i,
column: columnId
};
//Push item object into items array
items.push(item);
});
});
//Assign items array to sortorder JSON variable
var sortorder = { items: items };
//Pass sortorder variable to server using ajax to save state
$.post('/Widgets/SaveLayout', 'data=' + $.toJSON(sortorder), function (response) {
if (response == "success")
$("#console").html('<div class="success">Saved</div>').hide().fadeIn(1000);
setTimeout(function () {
$('#console').fadeOut(1000);
}, 2000);
});
alert(sortorder);
}
I am willing to consider alternative ways to do this, as I may not have chosen the best way to do this.
Phil Haack's blog post http://haacked.com/archive/2010/04/15/sending-json-to-an-asp-net-mvc-action-method-argument.aspx specifically handles the problem you are trying to solve and it works great.
Hope this helps.
Why not use a cookie? This would save you from having to pull that data back and forth from the server so much.

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