custom aspx page keeps lossing data on post back

Question

0.00/5 (No votes)

See more:

Hey all,

I am having one of the weirdest problems ever....

I have n custom aspx page that gets called from ms cr 4.0 button. When the page loads it poulates a dropdown box with all the coutrys then when i select a country it must load all the provinces for that country. It loads the country data when the form loads but when i select a country and the for does a postback to load the selected countrys provines it loses all the country data??? WHY ??

HTML :

ASP.NET

<asp:UpdatePanel ID="UpdatePanel1" runat="server">
        <ContentTemplate>
            <table style="border: none; width: 500px">
                <table style="border: none; width: 300px">
                    <tr>
                        <td class="style5">
                            Country<br />
                             
                        </td>
                        <td class="style8">
                            <asp:DropDownList ID="cboLocationCountry" runat="server" AutoPostBack="True" OnSelectedIndexChanged="cboLocationCountry_SelectedIndexChanged"
                                TabIndex="5" Width="196px">
                            </asp:DropDownList>
                        </td>
                    </tr>
                    <tr>
                        <td class="style5">
                            Province<br />
                             
                        </td>
                        <td class="style8">
                            <asp:DropDownList ID="cboLocationProvince" runat="server" AutoPostBack="True" Width="196px"
                                     OnSelectedIndexChanged="cboLocationProvince_SelectedIndexChanged" TabIndex="6">
                            </asp:DropDownList>
                        </td>
        </ContentTemplate>
</asp:UpdatePanel>

Page Load :

C#

     if (!IsPostBack)
{
    // clear country list
    //load all vehicles from crm db and populate dropdown
    cboLocationCountry.Items.Clear();
    loadCRMLookups("country", cboLocationCountry, "");
}

And loading the province data when a country is selected:

C#

protected void cboLocationProvince_SelectedIndexChanged(object sender, EventArgs e)
{
     // load selected province town's
    cboLocationTown.Items.Clear();
    cboLocationSuburb.Items.Clear();
    cboLocationZone.Items.Clear();
    loadCRMLookups("town", cboLocationTown, cboLocationProvince.SelectedValue);
    loadCRMLookups("zone", cboLocationZone, cboLocationProvince.SelectedValue);
    loadCRMLookups("suburb", cboLocationSuburb, cboLocationTown.SelectedValue);
}

Posted 16-Mar-12 1:25am

Ryno Engelbrecht

Add a Solution

2 solutions

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

BobJanova · Answer 1 · 2012-03-16T01:49:00

I don't think 'Items' is preserved across postbacks. (That would be a very large amount of data to send back to the server, in most cases unnecessarily.) If you set it in PageInit instead of PageLoad then server-side magic might keep hold of it for you, otherwise you'll have to cache the result of the lookup in the session and rebuild the Items array in posted back pages as well. In this case you should definitely do it in Init (not Load) so the posted back value for SelectedItem works.

As a side note, pages like this are extremely annoying, particularly if you have some latency on your connection. I strongly advise you to either make these free text fields or at least to use AJAX to rebuild the contents of secondary options.

sjelen · Answer 2 · 2012-03-16T02:04:00

Solution 2

Alternatively, instead of manually populating cboLocationCountry you can use one of the DataSource controls and bind cboLocationCountry to it.

Posted 16-Mar-12 2:04am

sjelen