I use Page-/WebMethods for handling actuallisize data every x seconds.
Normaly I have 1 Object created on my won, which I get back with 3 informations: time / name / price.
Now I build a site with x members of my object is needed, so:
can I easily get a List<> of my own object back to JavaScript
how can I access specific rows, I mean, how I know that the time of row 1 in my list is for time of 1 in the site?
Return the result as JSON string and then parse that in client side.
I do not think, JavaScript would be able to detect if its a List<>. JSON is the way to send and receive data via PageMethods in ASP.NET Ajax. Did you check this link which uses array to send and receive data, http://forums.asp.net/p/1222967/2198696.aspx#2198696.
Okay... ahm... it's nothing special to get Lists back over JavaScript... I only make a funny syntax error.
So if someone is interessted:
<script type="text/javascript" language="javascript">
function UpdateAll()
{
setTimeout("UpdateAll()", 99990);
PageMethods.Update(OnSucceeded);
}
function OnSucceeded(result, userContext, methodName)
{
alert(result.detailsList[0].Preis);
}
[WebMethod(EnableSession = true)]
public static object Update()
{
Business.AuctionInformationDetails details = new Business.AuctionInformationDetails();
List<Business.AuctionInformationDetails> detailsList = new List<Business.AuctionInformationDetails>(); ;
//Fill list
return new
{
detailsList = detailsList
};
}
(AuctionInformationDetails are only an object with 3 string).
Related
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've just moved to web development and need to know how i can implement below requirement using asp.net and vb.net.
I have three fields in a form which are filled by users. Based on these three values, i need to auto-populate the 4th field. I have planned to implement this in the following way
Write a separate class file with a function to calculate the possible values for the 4th fields based on 1st 3 inputs. This function can return some where between 1-10 values. So I've decided to use drop-down for 4th field, and allow users to select the appropriate value.
Call the above function in onchange function of 3rd field and take and use the return values to populate the 4th field. I'm planning to get the return values in array field.(Does this need a post back?)
Please let me know how if there is better way to implement this.
Thanks.
You may want to consider doing this with Javascript. You could read and control the fields pretty easily with pure Javascript, or using a nice library like jQuery (my favorite). If you did it this way, no post-back would be required and the 4th field would update immediately. (Nice for your users)
You can also do it with ASP.NET for the most part. "onchange" in ASP.NET still requires Javascript as far as I know, it just does some of it for you. A post-back will definitely happen when you change something.
You need javascript or to set autopostback=true on your form elements.
From a user perspective the best thing is to use javascript to populate the field for display, BUT when the form is submitted use your backend function to validate it. This will make sure the user didn't change the value.
An easy way is to use jQuery for the UI (that way you don't have to worry about long winded javascript and deal with browser compatibility as it's already taken care of for you) and have it call to the server for the data. For the server, your easiest route is to return JSON for looping values.
Include your jQuery:
<script type="text/javascript" src="https://ajax.googleapis.com/ajax/libs/jquery/1.4.3/jquery.min.js"></script>
Then add in a handle for the JavaScript:
<script type="text/javascript">
function autoPopulate() {
var value1 = $('#ddl1').val();
var value2 = $('#ddl2').val();
var value3 = $('#ddl3').val();
var url = 'path/to/your/file.aspx?value1=' + value1 + '&value2=' + value2 + '&value3=' + value3;
$.getJSON(url, function(data) {
data == null ? return false : data = eval(data);
var ddl = $('#ddl4')[0];
for (i = 0; i < data.length; i++) {
var option = new Option(data[i][0], data[i][1]);
if ($.browser.msie) {
ddl.add(option);
} else {
ddl.add(option, null);
}
}
}
}
</script>
(Yes, I know I used a native loop but I'm little lazy here today :) )
Now, for your server side code you'll want your code your page to return data in the format of:
[['value1','text1'],['value2','text2'],['value3','value3']]
so something like:
<script type="vb" runat="server">
Private Sub Page_Init()
// get your data
// loop through it and add in values
// ex.
Dim result As String = "[" //start multi-dimensional array
For Each Item As String In data
result += String.Format("['{0}','{1}'],", _value, _text)
Next
result = result.SubString(0, result.Length - 1) // removes trailing comma
result += "]" // closes off m-array
Response.Write(result)
Response.Flush()
End Sub
</script>
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.
In a Flex application I am trying to turn an Object into a QueryString such as name1=value1&name2=value2... But I am having trouble getting the names of the Objects children. How do I enumerate the names instead of the values?
Thanks
I'm guessing you're doing a for each(in) loop. Just do a normal for(in) loop and you'll get the names instead of the values:
for(var name:String in obj) {
var value:* = obj[name];
// do whatever you need
}
Ok, first off, if you need that query string to actually query a server, you don't really need to get it yourself as this code will query the server for you
protected function callSerivce():void
{
var o:Object = new Object();
o.action = "loadBogusData";
o.val1 = "dsadasd";
service.send(o);
}
<mx:HTTPService id="service" url="http://www.somewhere.com/file.php" method="GET" showBusyCursor="true"/>
Will make a call to the server like this: http://www.somewhere.com/file.php?action=loadBogusData&val1=dsadasd
But in case you really want to analyze the object by hand, try using ObjectUtil.getClassInfo, it returns a lot of information including all the fields (read more on LiveDocs).
I've created an ASP.Net user control that will get placed more than once inside of web page. In this control I've defined a javascript object such as:
function MyObject( options )
{
this.x = options.x;
}
MyObject.prototype.someFunction=function someFunctionF()
{
return this.x + 1;
}
In the code behind I've created MyObject in a startup script --
var opts = { x: 99 };
var myObject = new MyObject( opts );
When a certain button in the control is pressed it will call myObject.someFunction(). Now lets say the value of x will be 99 for one control but 98 for another control. The problem here is that the var myObject will be repeated and only the last instance will matter. Surely there's a way to make the var myObject unique using some concept I've haven't run across yet. Ideas?
Thanks,
Craig
Your Javascript like this:-
function MyObject(options) { this.x = options.x; }
MyObject.prototype.someFunction = function() { return this.x + 1; }
MyObject.create(id, options) {
if (!this._instances) this._instances = {};
return this._instances[id] = new MyObject(options);
}
MyObject.getInstance(id) { return this._instances[id]; }
Your startup javascript like this:-
MyObject.create(ClientID, {x: 99});
Other code that needs to use an instance (say in the client-side onclick event)
String.Format("onclick=\"MyObject.getInstance('{0}').someFunction()\", ClientID);
Note the low impact on the clients global namespace, only the MyObject identifier is added to the global namespace, regardless of how many instances of your control are added to the page.
If it is just one value, why not have the function take it as a parameter and build your onclick handler so that it puts the correct value in for each control. If it is more complex than that, then consider making options an array and, for each control, insert the correct options into the spot in the array that corresponds to each particular control. Then pass the proper index into the array into the function.
I do this by using ScriptManager.RegisterClientScriptBlock to register a string as a JavaScript block on the client side. I can then modify my script string using {0}, {1}..,{n} place holders to inject necessary ids. It depends on the structure of your code as to if this is the most elegant fashion, but it works in a pinch. You could then inject variable names using references to Me.ClientID.
You can make the value of "x" static and access it anywhere in the code, such as:
function MyObject( options ) { MyObject.x = options.x; }
MyObject.x = 99; // static
MyObject.prototype.someFunction = function () { return MyObject.x + 1; }
This way you can access MyObject.x anywhere in your code, even without re-instanciating MyObject.
Excellent solution Anthony. The other solutions offered were as good and I did consider them but I was looking for something a little more elegant like this solution.
Thanks!