We Keep Coding

Put a DropDownList instead of TextBox in DetailsView control

I have an EntityDataSource control that is bind to an edmx file.
I create a detailsview and set it's DataSource property to entitydatasource control.
now I want to put a DropDownList instead of TextBox for "no_region_code" in Inserting mode.
Here is what I found from internet but it does not insert the contents of dropdownlist to the table when i click on insert button of detailsview.
<asp:TemplateField HeaderText="no_region_code" SortExpression="no_region_code">
<InsertItemTemplate>
<asp:DropDownList ID="drp_region_list" runat="server" DataMember="no_region_code">
<asp:ListItem Value="41">tabriz</asp:ListItem>
<asp:ListItem Value="21">tehran</asp:ListItem>
</asp:DropDownList>
</InsertItemTemplate>
</asp:TemplateField>
How can I put a dropdownlist instead of these textboxes?

You didn't bind any property on that DropDownList. Try something like this
<asp:DropDownList ID="drp_region_list" runat="server" SelectedValue='<%# Bind("no_region_code")%>' DataMember="no_region_code">
<asp:ListItem Value="41">tabriz</asp:ListItem>
<asp:ListItem Value="21">tehran</asp:ListItem>
</asp:DropDownList>
EDIT : bind represent a way to link your property from the code behind (or model) to an asp control. This binding is bidirectional. For example, if you already have a value for no_region_code property in the code behind, the dropdown will already have that value selected on the view. Google asp.net data binding and you'll find a lot of examples and some more in depth explanations.

Change blank selection in drop down list?

I have a databound dropdown list on my page. The first value in the selection list is blank. Is there a way that I can change it so that the first selection says "Unassigned" instead of blank? I've tried the following, but it didn't work:
// Insert 'Unassigned' value for artist dropdown
ddlArtists.Items.Insert(0, "Unassigned");
After inserting the above code, the list still appears unchanged, with the first selection value being a blank. Any pointers would be great! Thank you!
EDIT: Here is the code for the dropdown:
<asp:DropDownList ID="ddlArtists" runat="server" Width="130px" TabIndex="5"
OnSelectedIndexChanged="ddlArtists_SelectedIndexChanged"
DataSourceID="sqldsArtist" DataTextField="Name" DataValueField="ID"
OnDataBound="ddl_DataBound"
AutoPostBack="True">

You don't need to do it on the CodeBehind. Just do it like that:
<asp:DropDownList ID="ddlArtists" runat="server" AppendDataBoundItems="true">
<asp:ListItem Text="Unassigned" Value="0" Selected="true" />
</asp:DropDownList>
The AppendDataBoundItems property defines whether the contents of the DropDownList should be cleared out before data binding.
Don't forget to check for a PostBack when you're data binding it, to avoid duplicates.

Set the SelectedIndex property of your DropDownList to 0.

asp.net ListView sort by column

I have a list view binded to a data source.
How can I enable sorting by column?
So when clicking the column title once it sorts by ascending, click it again it sorts by descending.
Is there anything in the wizard that can be setup or it all needs to be done programatically?

If you are using a data source control then sorting can be implemented in the ListView control without having to write a single line of code - it is all handled automatically by the ListView and its data source control. Of course, in more advanced scenarios we may need to manually sort the data or programmatically.
In the following example, ListView will be sorted by ProductName and UnitPrice. simply add two LinkButtons in the ListView's LayoutTemplate with appropriate CommandName and CommandArgument property values.
<asp:ListView ID="ProductList" runat="server" DataSourceID="ProductDataSource">
<LayoutTemplate>
<h3>Product Listing</h3>
<asp:LinkButton runat="server" ID="SortByName" CommandName="Sort"
CommandArgument="ProductName">Sort by Name</asp:LinkButton>
| <asp:LinkButton runat="server" ID="SortByPrice" CommandName="Sort"
CommandArgument="UnitPrice">Sort by Price</asp:LinkButton>
<blockquote>
<asp:PlaceHolder runat="server" ID="itemPlaceholder"></asp:PlaceHolder>
</blockquote>
</LayoutTemplate>
...
</asp:ListView>
If a user clicks the "Sort by Price" link twice in a row, the first time the products will be sorted in ascending order (from cheapest to most expensive), but the second time the sort order will reverse.

That depends on the DataSource you are using. If the Data Source allows sorting, it can be set up in the way described here http://msdn.microsoft.com/en-us/library/sa88ktts.aspx . Otherwise you have to handle sorting yourself programatically. Usually that is even easier than the automatical approach.

Bind SelectedValue of ASP.net DropDownList to nested property

(first of all, it seems this is a subject that is discussed many times before, but I can't find a proper answer for my case)
I have a asp.net FormView with a DropDownList for the selection of a month. The FormView is data bound to an ObjectDataSource.
<asp:DropDownList ID="MonthsList" DataSourceID="MonthsListDataSource" DataTextField="Value" DataValueField="Key" SelectedValue='<%# Bind("OrderDate.Month") %>' Width="100" runat="server" />
I like to bind the selected value to the nested property 'Month' of 'OrderDate' as shown above. The property OrderDate is of type DateTime. The error I'm getting while binding to a nested property is:
A call to Bind was not well formatted. Please refer to documentation for the correct parameters to Bind.
What is the best solution to be able to bind to a nested propety?
Thanks in advance.

Are you retrieving data from DataSourceID="MonthsListDataSource" and tryingo to bind it to another DataBase field (SelectedValue='<%# Eval("OrderDate.Month") %>') ?
In my application a do this like this:
<asp:DropDownList ID="MonthsList" DataSourceID="MonthsListDataSource" DataTextField="Value" DataValueField="Key" SelectedValue='<%# Eval("MonthsListDataSource.Month") %>' Width="100" runat="server" />
And when Updating a retrieve de DropDownList with find control, get its selected value, associate it to other table (OrderDate.Month) and save it.
Sorry my answer, but i dont know if a undertand it.

What about using Eval keyword
<asp:DropDownList ID="MonthsList" DataSourceID="MonthsListDataSource" DataTextField="Value" DataValueField="Key" SelectedValue='<%# Eval("OrderDate.Month") %>' Width="100" runat="server" />

How to set DropDownList's selected value inside a Repeater?

I need to create a group of DropDownLists to show and allow change of a property group for an item.
I have the following code on my ASP page.
<asp:Repeater runat="server" ID="repeaterProperties">
<ItemTemplate>
<p><asp:DropDownList runat="server" ID="ddProperty" OnInit="ddProperty_OnInit" /><p>
</ItemTemplate>
</asp:Repeater>
The ddProperty_OnInit populates the DropDownList with all the possible values with a database query.
How can I set the selected value of each created DropDownList according to the Repeater's source data?
Let's say, for example, that we have the possible property values of A, B and C.
If the database output for the Repeater contains two of those values, A and B, the Repeater outputs two DropDownLists, both with all 3 values availabla and the first one with A as selected value and the second one with B as selected value.
Edit:
It seems that adding OnItemDataBound="repeater_ItemDataBound" to the Repeater and selecting the appropriate value in there is not the way to go in my case. This is because I also need to save the possibly changed values to a database.
The ItemDataBound event of the Repeater is fired before the OnClick event on a Button and changes the selected values to their old values before the new selections can be saved.
Any suggestion on how to work around this?
Current code:
<asp:Repeater runat="server" ID="repeaterJako" OnItemDataBound="repeater_ItemDataBound">
<ItemTemplate>
<asp:DropDownList id="ddJako" runat="server" OnInit="ddJako_OnInit">
</asp:DropDownList><br />
</ItemTemplate>
</asp:Repeater>
<asp:Button runat="server" id="updateButton" Text="Save" OnClick="update_OnClick" />
In the code-behind, ddJako_OnInit populates the drop down list with all the possible choises, while the repeater_ItemDataBound uses the method suggested by Bryan Parker to select the proper value.

Maybe I'm misunderstanding something about your question... but it seems like this is exactly what OnItemDataBound is for. :)
Use FindControl to get a reference to your DropDownList in the event handler. Also check to make sure the item is not the header/footer. The example from MSDN does both these things:
http://msdn.microsoft.com/en-us/library/system.web.ui.webcontrols.repeater.onitemdatabound.aspx

In regard the problem I specified in my edit, the time of the DataBind plays an important role. I used to do the databinding in the Page_Init event, which caused the repeater_ItemDataBound event to be fired before the button_OnClick event.
The solution was to move the databinding to the Page_PreRender event.
The population of the DropDownList with all the choises is still done in its OnInit event.