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POGridview binding clears unexpectedly
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  1. POGridview binding clears unexpectedly
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    copied!<p>I have a problem with my gridview. I have searched alot for the solution but can't find any answers. I think I have located the problem to be that the gridview is no longer bound when I press the update button - which results in null values. I thought it was enough to bind at RowEditing. Where else can I bind my gridview?</p> <p>See the markup below:</p> <pre><code> &lt;asp:GridView ID="ProductGridView" runat="server" AllowPaging="True" AllowSorting="True" AutoGenerateColumns="False" DataKeyNames="Id" OnRowEditing="ProductGridView_RowEditing" OnRowCancelingEdit="ProductGridView_RowCancelingEdit" OnRowUpdating="ProductGridView_RowUpdating" OnRowDeleting="ProductGridView_RowDeleting" OnDataBound="ProductGridView_DataBound" OnRowDataBound="ProductGridView_RowDataBound"&gt; &lt;Columns&gt; &lt;asp:CommandField ShowDeleteButton="True" ShowEditButton="True" CausesValidation="false" /&gt; &lt;asp:TemplateField HeaderText="Name" SortExpression="Name"&gt; &lt;EditItemTemplate&gt; &lt;asp:TextBox ID="txtName" runat="server" Text='&lt;%# Bind("Name") %&gt;'&gt;&lt;/asp:TextBox&gt; &lt;/EditItemTemplate&gt; &lt;ItemTemplate&gt; &lt;asp:Label ID="lblName" runat="server" Text='&lt;%# Eval("Name") %&gt;'&gt;&lt;/asp:Label&gt; &lt;/ItemTemplate&gt; &lt;/asp:TemplateField&gt; &lt;asp:TemplateField HeaderText="Quantity" SortExpression="Quantity"&gt; &lt;EditItemTemplate&gt; &lt;asp:TextBox ID="txtQuantity" runat="server" Text='&lt;%# Bind("Quantity") %&gt;'&gt;&lt;/asp:TextBox&gt; &lt;/EditItemTemplate&gt; &lt;ItemTemplate&gt; &lt;asp:Label ID="lblQuantity" runat="server" Text='&lt;%# Eval("Quantity") %&gt;'&gt;&lt;/asp:Label&gt; &lt;/ItemTemplate&gt; &lt;/asp:TemplateField&gt; &lt;asp:TemplateField HeaderText="Family" SortExpression="Family.Name"&gt; &lt;EditItemTemplate&gt; &lt;asp:DropDownList ID="ddlFamily" runat="server" OnInit="ddlFamily_Init"&gt; &lt;/asp:DropDownList&gt; &lt;/EditItemTemplate&gt; &lt;ItemTemplate&gt; &lt;asp:Label ID="lblFamily" runat="server" Text='&lt;%# Eval("Family.Name") %&gt;'&gt;&lt;/asp:Label&gt; &lt;/ItemTemplate&gt; &lt;/asp:TemplateField&gt; &lt;/Columns&gt; &lt;/asp:GridView&gt; </code></pre> <p>And the code-behind:</p> <pre><code> protected void Page_Load(object sender, EventArgs e) { if (!Page.IsPostBack) { BindGridView(_productRepo.GetAll()); } } private void BindGridView(object source) { ProductGridView.DataSource = source; ProductGridView.DataBind(); } protected void ProductGridView_RowEditing(object sender, GridViewEditEventArgs e) { ProductGridView.EditIndex = e.NewEditIndex; BindGridView(_productRepo.GetAll()); // GetAll returns an IEnumerable. rowCount = ProductGridView.Rows.Count; // Count is 6 here, which is correct. } protected void ProductGridView_RowUpdating(object sender, GridViewUpdateEventArgs e) { rowCount = ProductGridView.Rows.Count; // Count is 0 here. //BindGridView(_productRepo.GetAll()); // Tried to rebind which works but getting the old values obviously. //rowCount = ProductGridView.Rows.Count; // Count is 6 here. // Get the controls - all is null. Works ok when I use BindGridView above. TextBox txtName = FindChildControl&lt;TextBox&gt;(this.Page, "txtName"); TextBox txtQuantity = FindChildControl&lt;TextBox&gt;(this.Page, "txtQuantity"); DropDownList ddlFamily = FindChildControl&lt;DropDownList&gt;(this.Page, "ddlFamily"); // More code to populate a new product and bind the gridview again etc. } </code></pre> <p>I also have a RowDataBound method. Can this contribute to the problem?</p> <pre><code>protected void ProductGridView_RowDataBound(object sender, GridViewRowEventArgs e) { if (e.Row.RowType == DataControlRowType.DataRow &amp;&amp; (e.Row.RowState &amp; DataControlRowState.Edit) == DataControlRowState.Edit) { DropDownList ddl = (DropDownList)e.Row.FindControl("ddlFamily"); ddl.DataSource = _familyRepo.GetAll().Select(f =&gt; f.Name); ddl.DataBind(); Product product = _productRepo.FindSingle(p =&gt; p.Id == (int)ProductGridView.DataKeys[e.Row.RowIndex].Value); ddl.SelectedIndex = (int)product.FamilyID - 1; } } </code></pre>
 

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