Develop Reference

setting selected option in asp.net using c#

I have a following code in aspx page
<asp:DropDownList ID="txtSupplierCountry" class="form-control" Width="230px" runat="server">
<asp:ListItem Text="Select gender" Value="0"></asp:ListItem>
<asp:ListItem Text="male" Value="0"></asp:ListItem>
<asp:ListItem Text="female" Value="1"></asp:ListItem>
</asp:DropDownList>
I have a value in database as male/female. I need to set this text using C# code. Basically I am trying to set selected option based on the text from database. I am not getting an idea. I have tried following code but it doesn't work.
String t = "male" // coming from db
txtSupplierCountry.Items.FindByText(t).Selected = true;

when you are saving data Male and Female then why did you keep dropdown values in number like 1,2 etc, change code like this.
<asp:DropDownList ID="txtSupplierCountry" class="form-control" Width="230px" runat="server">
<asp:ListItem Text="Select Country" Value="0"></asp:ListItem>
<asp:ListItem Text="male" Value="male"></asp:ListItem>
<asp:ListItem Text="female" Value="female"></asp:ListItem>
then
txtSupplierCountry.SelectedValue="male";

Get and split multiple values from database field and view them as selected in a multiple select listbox

I want to get the values in a string from a database which i can do and my result is
string strValues = "'value1','value2','value3'";
i know we can split them using the split function. But the problem is how to mark them in the list box.
<asp:ListBox ID="lstValues" runat="server" SelectionMode="Multiple">
<asp:ListItem Value="-1">[``Select]</asp:ListItem>
<asp:ListItem Value="1">value 10</asp:ListItem>
<asp:ListItem Value="2">value 9</asp:ListItem>
<asp:ListItem Value="3">value 3</asp:ListItem>
<asp:ListItem Value="4">value 2</asp:ListItem>
<asp:ListItem Value="5">value 1</asp:ListItem>
</asp:ListBox>

<asp:ListBox ID="lstValues" runat="server" SelectionMode="Multiple">
<asp:ListItem Value="-1">[``Select]</asp:ListItem>
<asp:ListItem Value="1">value 10</asp:ListItem>
<asp:ListItem Value="2">value 9</asp:ListItem>
<asp:ListItem Value="3">value 3</asp:ListItem>
<asp:ListItem Value="4">value 2</asp:ListItem>
<asp:ListItem Value="5">value 1</asp:ListItem>
</asp:ListBox>
add Selected="true" on the Items you want to be checked!
Example: <asp:ListItem Value="5" selected="true">value 1</asp:ListItem>
you can also use Checked="true" for list boxes

Hidden/Visible display depending on C# Dropdown selection

To be brief, I need the Textbox with ID="textComments" to only appear when the dropdown option of 'Other' is selected from the dropdown, and then disappear if another selection is made. I could do this with JS but it needs to be in C#.
<asp:DropDownList runat="server" ID="dropEnquiryType" CssClass="dropdownRequestList">
<asp:ListItem Value="Customer Services" Text="Customer Services"></asp:ListItem>
<asp:ListItem Value="Website" Text="Website"></asp:ListItem>
<asp:ListItem Value="Contract" Text="Contract Hire"></asp:ListItem>
<asp:ListItem Value="Other" Text="Other"></asp:ListItem>
</asp:DropDownList>
<asp:label runat="server" ID="lblComments" AssociatedControlID="textComments" CssClass="textLabel">Comments:</asp:label>
<asp:TextBox runat="server" MaxLength="200" TextMode="MultiLine" Columns="40" Rows="4" ID="textComments" Wrap="true" CssClass="textComments"></asp:TextBox>
And help would be greatly appreciated.

Make the DropDownList first AutoPostBack=true
handle it's SelectedIndexChanged-event
Switch visibility of both controls there
aspx:
<asp:DropDownList AutoPostBack="true" OnSelectedIndexChanged="dropEnquiryType_Changed" runat="server" ID="dropEnquiryType" CssClass="dropdownRequestList">
<asp:ListItem Value="Customer Services" Text="Customer Services"></asp:ListItem>
<asp:ListItem Value="Website" Text="Website"></asp:ListItem>
<asp:ListItem Value="Contract" Text="Contract Hire"></asp:ListItem>
<asp:ListItem Value="Other" Text="Other"></asp:ListItem>
</asp:DropDownList>
codebehind:
protected void dropEnquiryType_Changed(Object sender, EventArgs e)
{
lblComments.Visible = dropEnquiryType.SelectedValue == "Other";
textComments.Visible = lblComments.Visible;
}

If you absolutely have to do this within C#, then a simple check in PreRender should be sufficient:
textComments.Visible = (dropEnquiryType.SelectedValue == "Other");
This will also require you to set AutoPostback on dropEnquiryType, though, which uses ... JavaScript!

DropdownList with Multi select option?

I have a DropDownList as following
<asp:DropDownList ID="ddlRoles" runat="server" AutoPostBack="True" Width="150px">
<asp:ListItem Value="9" Text=""></asp:ListItem>
<asp:ListItem Value="0">None</asp:ListItem>
<asp:ListItem Value="1">Ranu</asp:ListItem>
<asp:ListItem Value="2">Mohit</asp:ListItem>
<asp:ListItem Value="3">Kabeer</asp:ListItem>
<asp:ListItem Value="4">Jems</asp:ListItem>
<asp:ListItem Value="5">Jony</asp:ListItem>
<asp:ListItem Value="6">Vikky</asp:ListItem>
<asp:ListItem Value="7">Satish</asp:ListItem>
<asp:ListItem Value="8">Rony</asp:ListItem>
</asp:DropDownList>
I want to select Multiple name at once suppose I want to select Ranu Mohit or Ranu Kabeer Vikky, How its possible?

asp:DropDownList does not support multiple selects:
VerifyMultiSelect():
Always throws an HttpException exception because multiple selection is not supported for the DropDownList control.
You can use asp:ListBox with SelectionMode="Multiple" instead:
<asp:ListBox SelectionMode="Multiple" ID="lbRoles" runat="server" AutoPostBack="True" Width="150px">
<asp:ListItem Value="9" Text=""></asp:ListItem>
<asp:ListItem Value="0">None</asp:ListItem>
<asp:ListItem Value="1">Ranu</asp:ListItem>
<asp:ListItem Value="2">Mohit</asp:ListItem>
<asp:ListItem Value="3">Kabeer</asp:ListItem>
<asp:ListItem Value="4">Jems</asp:ListItem>
<asp:ListItem Value="5">Jony</asp:ListItem>
<asp:ListItem Value="6">Vikky</asp:ListItem>
<asp:ListItem Value="7">Satish</asp:ListItem>
<asp:ListItem Value="8">Rony</asp:ListItem>
</asp:ListBox>

After filling a DropDownList with date from a database, how can I set the default selection to "Select One"?

This is what I tried...
ddlClientsInSearchResult.DataSource = dtClients;
ddlClientsInSearchResult.DataValueField = dtClients.Columns[0].ToString();
ddlClientsInSearchResult.DataTextField = dtClients.Columns[1].ToString();
ddlClientsInSearchResult.DataBind();
ddlClientsInSearchResult.Items.Insert(0, "Select One");
so that the first item in the list is "Select One", but this doesn't seem to be working for me. This is in the code behind an .aspx page, so I was thinking maybe there was a way I could do it over there...but my internet searching has not turned up a solution.
<asp:DropDownList ID="ddlClients" runat="server" Font-Size="8pt" Font-Names="Tahoma"
Width="200px" AutoPostBack="true" OnSelectedIndexChanged="ddlClients_SelectedIndexChanged">
</asp:DropDownList>
That's the ASP.net code for the DropDownBow that I'm trying to default to "Select One".
Thanks for the help!

Remove this ddlClientsInSearchResult.Items.Insert(0, "Select One"); from code behind and do like...
<asp:DropDownList ID="ddlClients" runat="server" Font-Size="8pt" Font-Names="Tahoma"
Width="200px" AutoPostBack="true" OnSelectedIndexChanged="ddlClients_SelectedIndexChanged"
AppendDataBoundItems="true">
<asp:ListItem Text="Select one" Value="0"></asp:ListItem>
</asp:DropDownList>

Just add this to your markup:
<asp:DropDown>
<asp:ListItem Text="Select One" Value="" Selected="true">Select One</asp:ListItem>
</asp:DropDown/>

the code that worked for me is as below
ddlMonth.SelectedIndex = Convert.ToDateTime(row["cstDOB"].ToString()).Month;
ddlYear.SelectedItem.Text = Convert.ToDateTime(row["cstDOB"].ToString()).Year.ToString();
ddlState.SelectedItem.Text = row["cstState"].ToString();

Add "Select One" as an item declaratively and Use the AppendDataBoundItems="true"
<asp:DropDownList ID="ddlClients" runat="server" AppendDataBoundItems="true" AutoPostBack="true" >
<asp:ListItem Value="0">Select One</asp:ListItem>
</asp:DropDownList>