Databound drop down list - initial value

Question

How do I set the initial value of a databound drop down list in ASP NET    For instance  I want the values  but the first value to display should be -- Select One ---  with a null value

User · Answer

dropdownlist Items Insert 0  new Listitem  --Select One--    0

User · Answer

Add an item and set its  Selected  property to true  you will probably want to set  appenddatabounditems  property to true also so your initial value isn t deleted when databound   If you are talking about setting an initial value that is in your databound items then hook into your ondatabound event and set which index you want to selected true you will want to wrap it in  if not page isPostBack then       though  Protected Sub DepartmentDropDownList DataBound ByVal sender As Object  ByVal e As    System EventArgs  Handles DepartmentDropDownList DataBound     If Not Page IsPostBack Then         DepartmentDropDownList SelectedValue    somevalue      End If End Sub

User · Answer

hi friend in this case you can use the  AppendDataBound  true    and after this use the list item  for e g     lt asp DropDownList ID  DropDownList1  runat  server  AppendDataBoundItems  true  gt       lt asp ListItem Text  --Select One--  Value      gt      lt  asp DropDownList gt    but the problem in this is after second time select data are append with old data

User · Answer

I think what you want to do is this    lt asp DropDownList ID  DropDownList1  runat  server  AppendDataBoundItems  true  gt       lt asp ListItem Text  --Select One--  Value      gt      lt  asp DropDownList gt    Make sure the  AppendDataBoundItems  is set to true or else you will clear the  --Select One--  list item when you bind your data   If you have the  AutoPostBack  property of the drop down list set to true you will have to also set the  CausesValidation  property to true then use a  RequiredFieldValidator  to make sure the  --Select One--  option doesn t cause a postback    lt asp RequiredFieldValidator ID  RequiredFieldValidator1  runat  server  ControlToValidate  DropDownList1  gt  lt  asp RequiredFieldValidator gt

User · Answer

I know this is old  but a combination of these ideas leads to a very elegant solution   Keep all the default property settings for the DropDownList  AppendDataBoundItems false  Items empty    Then handle the DataBound event like this   protected void dropdown DataBound object sender  EventArgs e        DropDownList list   sender as DropDownList      if  list    null          list Items Insert 0   --Select One--        The icing on the cake is that this one handler can be shared by any number of DropDownList objects  or even put into a general-purpose utility library for all your projects

User · Answer

To select a value from the dropdown use the index like this   if we have the    lt asp DropDownList ID  DropDownList1  runat  server  AppendDataBoundItems  true  gt  lt  asp DropDownList gt    you would use    DropDownList1 Items DropDownList1 SelectedIndex  Value   this would return the value for the selected index

User · Answer

What I do is set the text property of the drop down list AFTER I databind it   Something like this      protected void LoadPersonComboBox                 var p   new PeopleBLL             rcmbboxEditPerson DataSource   p GetPeople            rcmbboxEditPerson DataBind            rcmbboxEditPerson Text    Please select an existing person to edit              This makes the initial visible value of this dropdown show up  but not actually be a part of the drop down  nor is it a selectable

User · Answer

I know this already has a chosen answer - but I wanted to toss in my two cents  I have a databound dropdown list    lt asp DropDownList    id  country     runat  server     CssClass  selectOne     DataSourceID  country code     DataTextField  Name     DataValueField  CountryCode PK   gt  lt  asp DropDownList gt   lt asp SqlDataSource    id  country code     runat  server     ConnectionString   lt    ConnectionStrings DBConnectionString   gt     SelectCommand  SELECT CountryCode PK  CountryCode PK     -     Name AS N Name  FROM TBL Country ORDER BY CountryCode PK   gt  lt  asp SqlDataSource gt    In the codebehind  I have this -  which selects United States by default    if  this IsPostBack        handle posted data   else      country SelectedValue    US       The page initially loads based on the  US  value rather than trying to worry about a selectedIndex  what if another item is added into the data table - I don t want to have to re-code

[asp.net] Databound drop down list - initial value

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