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POADO.net Entity Gridview is null when RowUpdating event fired
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  1. POADO.net Entity Gridview is null when RowUpdating event fired
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    copied!<p>So I'm using ADO.net Entity Data model in an ASP.Net (C#) Web page. I am dynamically adding and retrieving data to my database using gridviews. I am using master pages, and my gridview is in a contentplaceholder. My only issue with this code is that when my RowUpdating event fires, the gridview is null. I can call by BindGV function, and then the rest of the code updates the database perfectly fine, with the original data from the database I just bound to it, since the database was not updated yet. In all events, if I change bindGV() to Gridview1.databind(), the gridview is null. I think the datasource the gridview is referencing is becoming null at the end of the event when the data connection is closed, is there anyway to prevent this? </p> <pre><code>&lt;asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="False" onrowcancelingedit="GridView1_RowCancelingEdit" onrowediting="GridView1_RowEditing" onrowupdating="GridView1_RowUpdating" onrowdatabound="GridView1_RowDataBound" &gt; &lt;Columns&gt; &lt;asp:TemplateField Visible="false"&gt; &lt;ItemTemplate&gt; &lt;asp:Label ID="lblId" runat="server" Text='&lt;%# Eval("id") %&gt;'&gt;&lt;/asp:Label&gt; &lt;/ItemTemplate&gt; &lt;EditItemTemplate&gt; &lt;asp:Label ID="lblId" runat="server" Text='&lt;%# Eval("id") %&gt;'&gt;&lt;/asp:Label&gt; &lt;/EditItemTemplate&gt; &lt;/asp:TemplateField&gt; &lt;asp:TemplateField HeaderText="Machine"&gt; &lt;ItemTemplate&gt; &lt;asp:Label ID="lblMachine" runat="server" Text='&lt;%# Eval("MachineName") %&gt;'&gt;&lt;/asp:Label&gt; &lt;/ItemTemplate&gt; &lt;EditItemTemplate&gt; &lt;asp:TextBox ID="txtMachine" runat="server" Text='&lt;%# Eval("MachineName") %&gt;'&gt;&lt;/asp:TextBox&gt; &lt;/EditItemTemplate&gt; &lt;ControlStyle Width="60px" /&gt; &lt;/asp:TemplateField&gt; &lt;asp:TemplateField HeaderText="Dept"&gt; &lt;ItemTemplate&gt; &lt;asp:Label ID="lblDept" runat="server" Text='&lt;%# Eval("WorkCenterFK") %&gt;'&gt;&lt;/asp:Label&gt; &lt;/ItemTemplate&gt; &lt;EditItemTemplate&gt; &lt;asp:DropDownList ID="ddldept" runat="server" &gt; &lt;/asp:DropDownList&gt; &lt;/EditItemTemplate&gt; &lt;ControlStyle Width="120px" /&gt; &lt;/asp:TemplateField&gt; &lt;asp:CommandField HeaderText="Actions" ShowEditButton="true" ShowDeleteButton="True" ControlStyle-Width="50px" CausesValidation="false"&gt; &lt;/asp:CommandField&gt; &lt;/Columns&gt; </code></pre> <p></p> <pre><code>protected void BindGV() { QualityEntities database = new QualityEntities(); GridView1.DataSource = (from m in database.Machines from d in database.Workcenters where m.WorkcenterFK == d.id select new { id = m.id, MachineName = m.MachineName, WorkCenterFK = d.WorkCenterName }); ; GridView1.DataBind(); } protected void Page_Load(object sender, EventArgs e) { if (!Page.IsPostBack) BindGV(); } protected void GridView1_RowEditing(object sender, GridViewEditEventArgs e) { GridView1.EditIndex = e.NewEditIndex; BindGV(); } protected void GridView1_RowCancelingEdit(object sender, GridViewCancelEditEventArgs e) { GridView1.EditIndex = -1; BindGV(); } protected void GridView1_RowUpdating(object sender, GridViewUpdateEventArgs e) { QualityEntities database = new QualityEntities(); BindGV(); Int32 id = Convert.ToInt32(((Label)GridView1.Rows[e.RowIndex].FindControl("lblId")).Text); DropDownList ddl = ((DropDownList)GridView1.Rows[e.RowIndex].FindControl("ddlDept")); TextBox txt = ((TextBox)GridView1.Rows[e.RowIndex].FindControl("txtMachine")); Machine mch = (from m in database.Machines where m.id == id select m).Single(); mch.MachineName = txt.Text; mch.WorkcenterFK = Convert.ToInt32(ddl.SelectedItem.Value); database.SaveChanges(); GridView1.EditIndex = -1; BindGV(); } protected void GridView1_RowDataBound(object sender, GridViewRowEventArgs e) { QualityEntities database = new QualityEntities(); DropDownList temp = (DropDownList)(e.Row.FindControl("ddlDept")); if (temp != null) { temp.DataSource = (from w in database.Workcenters select w); temp.DataTextField = "WorkCenterName"; temp.DataValueField = "id"; temp.DataBind(); Int32 id = Convert.ToInt32(((Label)e.Row.FindControl("lblId")).Text); } } </code></pre>
 

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