No this isn't a copy
of this question: http://stackoverflow.com/questions/654423/button-in-update-panel-is-doing-a-full-postback
I've got a drop down inside an update panel, and I am trying to get it to allow
the person using
the page to add users to a list that is bound to a gridview.
The list is a global variable, and on page_load I set that to
the gridview's datasource and databind it. However, anytime I click
the 'add a user' button, or
the button to remove
the user from
the list. It appears like it is doing a full post back even though all these elements are inside
the update Panel.
Code Behind:
Public accomplishmentTypeDao As New AccomplishmentTypeDao()
Public accomplishmentDao As New AccomplishmentDao()
Public userDao As New UserDao()
Public facultyDictionary As New Dictionary(Of Guid, String)
Public facultyList As New List(Of User)
Public associatedFaculty As New List(Of User)
Public facultyId As New Guid
Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
Page.Title = "Add a New Faculty Accomplishment"
ddlAccomplishmentType.DataSource = accomplishmentTypeDao.getEntireTable()
ddlAccomplishmentType.DataTextField = "Name"
ddlAccomplishmentType.DataValueField = "Id"
ddlAccomplishmentType.DataBind()
facultyList = userDao.getListOfUsersByUserGroupName("Faculty")
For Each faculty As User In facultyList
facultyDictionary.Add(faculty.Id, faculty.LastName & ", " & faculty.FirstName)
Next
If Not Page.IsPostBack Then
ddlFacultyList.DataSource = facultyDictionary
ddlFacultyList.DataTextField = "Value"
ddlFacultyList.DataValueField = "Key"
ddlFacultyList.DataBind()
End If
gvAssociatedUsers.DataSource = associatedFaculty
gvAssociatedUsers.DataBind()
End Sub
Protected Sub deleteUser(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.CommandEventArgs)
facultyId = New Guid(e.CommandArgument.ToString())
associatedFaculty.Remove(associatedFaculty.Find(Function(user) user.Id = facultyId))
gvAssociatedUsers.DataBind()
upAssociatedFaculty.Update()
End Sub
Protected Sub btnAddUser_Click(ByVal sender As Object, ByVal e As EventArgs) Handles btnAddUser.Click
facultyId = New Guid(ddlFacultyList.SelectedValue)
associatedFaculty.Add(facultyList.Find(Function(user) user.Id = facultyId))
gvAssociatedUsers.DataBind()
upAssociatedFaculty.Update()
End Sub
Markup:
<asp:ScriptManager ID="ScriptManager1" runat="server">
</asp:ScriptManager>
<asp:UpdatePanel ID="upAssociatedFaculty" runat="server"
UpdateMode="Conditional">
<ContentTemplate>
<p><b>Created By:</b> <asp:Label ID="lblCreatedBy" runat="server"></asp:Label></p>
<p><b>Accomplishment Type: </b><asp:DropDownList ID="ddlAccomplishmentType" runat="server"></asp:DropDownList></p>
<p><b>Accomplishment Applies To: </b><asp:DropDownList ID="ddlFacultyList" runat="server"></asp:DropDownList>
<asp:Button ID="btnAddUser" runat="server" Text="Add Faculty" /></p>
<p>
<asp:GridView ID="gvAssociatedUsers" runat="server" AutoGenerateColumns="false"
GridLines="None" ShowHeader="false">
<Columns>
<asp:BoundField DataField="Id" HeaderText="Id" Visible="False" />
<asp:TemplateField ShowHeader="False">
<ItemTemplate>
<span style="margin-left: 15px;">
<p><%#Eval("LastName")%>, <%#Eval("FirstName")%>
<asp:Button ID="btnUnassignUser" runat="server" CausesValidation="false"
CommandArgument='<%# Eval("Id") %>' CommandName="Delete" OnCommand="deleteUser" Text='Remove' /></p>
</span>
</ItemTemplate>
</asp:TemplateField>
</Columns>
<EmptyDataTemplate>
<em>There are currently no faculty associated with this accomplishment.</em>
</EmptyDataTemplate>
</asp:GridView>
</p>
</ContentTemplate>
</asp:UpdatePanel>
Now I thought
the point
of an update panel was to be able to update things inside
of it without doing a full post_back and reloading
the page. So if that's
the case, why is it calling page_load everytime I click
the buttons? I ran this code and debug and I see that even before any
of the code associated with button press fires, page_load runs again.
I tried putting
the gvAssociatedUser.Datasource = associatedFaculty and
the line below inside
the Page.IsPostBack check, that prevented
the page from working. I tried every combination
of settings
of the update panel for ChildrenAsTriggers and UpdateMode, and none
of them worked.
I know this is something simple, but all
the combinations I've tried won't get it to work. How can I make this thing work?
