Rowupdating not giving new values

gridview

I am working on a application where i am using rowupdating event of the gridview. I am using templatefield in my columns so i am not able to get the new values from the textboxws that i am having in the gridview. How can i get the new values from the textboxes. Following is my code in rowupdating:

protected void gviewTemplate_RowUpdating(object sender, GridViewUpdateEventArgs e)
{
    gviewTemplate.EditIndex = -1;
    string rowNum = ViewState["ID"].ToString();
    Label lbl2 = (Label)gviewTemplate.Rows[e.RowIndex].FindControl("lblTemplateName");
    Label lbl1 = (Label)gviewTemplate.Rows[e.RowIndex].FindControl("lblUploaded");

    TextBox txtTempName = (TextBox)gviewTemplate.Rows[e.RowIndex].FindControl("txtTemplateName");
    TextBox txtHeading = (TextBox)gviewTemplate.Rows[e.RowIndex].FindControl("txtHeading");
    TextBox txtCoupon = (TextBox)gviewTemplate.Rows[e.RowIndex].FindControl("txtCouponText");
    TextBox txtBrand = (TextBox)gviewTemplate.Rows[e.RowIndex].FindControl("txtBrandName");
    TextBox txtSearchText = (TextBox)gviewTemplate.Rows[e.RowIndex].FindControl("txtSearch");
    TextBox txtDiscount = (TextBox)gviewTemplate.Rows[e.RowIndex].FindControl("txtDiscount");
    TextBox txtStartDt = (TextBox)gviewTemplate.Rows[e.RowIndex].FindControl("txtStartDt");
}

i want to get the new values form these textboxes but it is always giving me old values. and yes, e.Newvalues is not giving me anything. It is always empty. This is small extract from my gridview design:

<asp:GridView runat="server" AutoGenerateColumns="False"  
                        ID="gviewTemplate" onrowdatabound="gviewTemplate_RowDataBound" DataKeyNames="F1"
                        onrowcommand="gviewTemplate_RowCommand" 
                        onrowediting="gviewTemplate_RowEditing" 
                        onrowcancelingedit="gviewTemplate_RowCancelingEdit" 
                        onrowupdating="gviewTemplate_RowUpdating" 
                        onrowdeleting="gviewTemplate_RowDeleting" 
                        onrowupdated="gviewTemplate_RowUpdated">
                        <Columns>
                            <asp:TemplateField HeaderText="Uploaded Image">
                            <EditItemTemplate>
                                <asp:LinkButton Text="Reload" runat="server" OnClick="lbtnReloadImage_Click" CommandName="reload" ID="lbtnReloadImage"></asp:LinkButton>
                            </EditItemTemplate>
                                <ItemTemplate>
                                    <table id="Table2" runat="server" width="100%" cellpadding="0" cellspacing="0" border="0">
                                        <tr>
                                            <td>
                                                <asp:Label Runat="server" Text='<%# Eval("Uploaded") %>' ID="lblUploaded"></asp:Label>
                                            </td>
                                        </tr>
                                    </table>
                                </ItemTemplate>
                            </asp:TemplateField>
                            <asp:TemplateField HeaderText="Template Name">
                                <ItemStyle VerticalAlign="Top" HorizontalAlign="Center" />
                                <EditItemTemplate>
                                    <asp:TextBox ID="txtTemplateName" Width="60" Runat="server" Text='<%# Eval("F1") %>'></asp:TextBox>
                                    <asp:RequiredFieldValidator ID="RequiredFieldValidator1" Runat="server" 
                                    ErrorMessage="You must provide a Product Name." ControlToValidate="txtTemplateName">*</asp:RequiredFieldValidator>
                                </EditItemTemplate>
                                <ItemTemplate>
                                    <table id="Table3" runat="server" width="100%" cellpadding="0" cellspacing="0" border="0">
                                        <tr>
                                            <td>
                                                <asp:Label ID="lblTemplateName" runat="server" Text='<%# Eval("F1") %>'></asp:Label>
                                            </td>
                                        </tr>
                                    </table>
                                </ItemTemplate>
                            </asp:TemplateField>
                            <asp:TemplateField HeaderText="Heading">
                                <ItemStyle VerticalAlign="Top" HorizontalAlign="Center" />
                                <EditItemTemplate>
                                    <asp:TextBox ID="txtHeading" Runat="server" Width="60" Text='<%# Eval("F2") %>'></asp:TextBox>
                                    <asp:RequiredFieldValidator ID="RequiredFieldValidator2" Runat="server" 
                                    ErrorMessage="You must provide a Product Name." ControlToValidate="txtHeading">*</asp:RequiredFieldValidator>
                                </EditItemTemplate>
                                <ItemTemplate>
                                    <table id="Table4" runat="server" width="100%" cellpadding="0" cellspacing="0" border="0">
                                        <tr>
                                            <td>
                                                <asp:Label ID="lblHeading" runat="server" Text='<%# Eval("F2") %>'></asp:Label>
                                            </td>
                                        </tr>
                                    </table>
                                </ItemTemplate>
                            </asp:TemplateField>
                            <asp:TemplateField HeaderText="Coupon Text">
                                <ItemStyle VerticalAlign="Top" HorizontalAlign="Center" />
                                <EditItemTemplate>
                                    <asp:TextBox ID="txtCouponText" Runat="server" Width="80" Text='<%# Bind("F3") %>'></asp:TextBox>
                                    <asp:RequiredFieldValidator ID="RequiredFieldValidator3" Runat="server" 
                                    ErrorMessage="You must provide a Product Name." ControlToValidate="txtCouponText">*</asp:RequiredFieldValidator>
                                </EditItemTemplate>
                                <ItemTemplate>
                                    <table id="Table5" runat="server" width="100%" cellpadding="0" cellspacing="0" border="0">
                                        <tr>
                                            <td>
                                                <asp:Label Runat="server" Text='<%# Bind("F3") %>' ID="lblCouponText"></asp:Label>
                                            </td>
                                        </tr>
                                    </table>
                                </ItemTemplate>
                            </asp:TemplateField>

Can anyone please tell me how to get the new values from these textboxes?

Best Answer

Don't Rebind the GridView, just Bind it if the page is not postback

Related Solutions

.net – Why does GridView Rowupdating event not capture the new values of textbox

You should use the two way binding here. I.e. Bind instead of Eval:

<asp:TextBox ID="txtId" runat="server" Text='<%# Bind("id") %>'></asp:TextBox>

Here is the link to documentation:

Data-Binding Expressions Overview

Here is my code behind:

protected void Page_Load(object sender, EventArgs e)
    {
        DataTable table = new DataTable();
        table.Columns.Add("Data");
        for(int i = 0; i < 20; i++)
            table.Rows.Add(new object[] { i });
        GridView1.DataSource = table;
    if(!IsPostBack)  // <<<<<<<<<<<<
        GridView1.DataBind();
    }
protected void GridView1_RowEditing(object sender, GridViewEditEventArgs e)
    {
        GridView1.EditIndex = e.NewEditIndex;
        GridView1.DataBind();
    }       

    protected void GridView1_RowUpdating(object sender, GridViewUpdateEventArgs e)
    {
        TextBox text = (TextBox)GridView1.Rows[e.RowIndex].FindControl("txtId");
    }

C# – GridView RowUpdating does not get the new values

Hoo boy.

You didn't ask this in your question, but you've written some smelly code here. I'll try to address your question, but I'm also going through some of the other problems here.

Without seeing your markup, it's hard for me to tell if you've created GridViewResult programmatically or if it's in your markup as well. I'm not exactly sure what TaskGridViewResult is either -- is this an event for GridViewResult? Do you have another GridView on your page, and you want to show GridViewResult based on some search criteria?

I'm also not sure why you put all of your GridView binding code in Page_Load. I see that you're checking GetPostBackControl to find the control that caused the PostBack -- this is a code smell. If your users have to click a specific "Search" button, you should isolate your GridView binding code within that button's Click event.

Anyway, as to TaskGridViewResult_RowUpdating:

It looks like you're trying to update GridViewResult's old values to the new values by setting its DataSource and then iterating through its data. You can't do that. What happens when you change your RowUpdating event to:

protected void TaskGridViewResult_RowUpdating(object sender, GridViewUpdateEventArgs e)
{
    GridViewResult.DataSource = (DataTable)Session["Result"];
    GridViewResult.DataBind();
}

Now, other asides:

Your switch statements are code smells. DropDownLists expose a property called SelectedValue -- if you have some default value that isn't a valid selection (like the first option in your DropDownList), then you can change your original code from:

if ((test.ID == "SumbitSearch") && (DropDownListFrom.Text != "") && (DropDownListTo.Text != "") && (SearchField.Text != ""))
{
    string from = string.Empty;
    string to = string.Empty;

    switch (DropDownListFrom.SelectedIndex)
    {
        case 0:
            from = DropDownListFrom.Items[0].Value;
            break;
        /* other cases */
    }

    switch (DropDownListTo.SelectedIndex)
    {
        case 0:
            to = DropDownListTo.Items[0].Value;
            break;
        /* other cases */
    }
    /* snip */
}

to:

if (test.ID == "SubmitSearch" && DropDownListFrom.SelectedIndex > 0 && DropDownListTo.SelectedIndex > 0 && SearchField.Text != "")
{
    string from = DropDownListFrom.SelectedValue;
    string to = DropDownListTo.SelectedValue;

    /* snip */
}

If you can, please post your markup. I can offer you some more specific help or advice if I can tell what Controls you have on your page, and how they interact.

Edit: I should also add that you should get in the habit of using String.IsNullOrEmpty(string variable), rather than comparing to "". Although this isn't as big of a problem when you're referencing the text from web controls, getting in the habit now will prevent you from serious headaches and inefficiently checking for null and empty later. If you're in .NET 4.0, you should have access to IsNullOrWhiteSpace(), which is (in my opinion) more useful on the web, where users are more likely to try to enter junk data.

Edit 2: In response to your additional details above:

In your RowUpdating event, you need to pull the new values out of the front-end controls, and then re-bind your data. It looks like your source code is pretty close to the MSDN source code here. The difference between your code and the code on MSDN is: - The MSDN code takes the new data from the edited row and updates the appropriate data in the Session variable with that new data. - The MSDN code has a BindData() function -- I'm not sure if this is what your DataBind() function is, however. - The MSDN code updates the GridView by re-binding the GridView to the appropriate data in the Session.

Frankly, I have some issues with the MSDN code. I really, really hate seeing code like: dt.Rows[row.DataItemIndex]["Id"] = ((TextBox)(row.Cells[1].Controls[0])).Text; To me, this is garbage, because it's so highly coupled to the order of your cells.

If I had written the code, I would explicitly create all the front-end controls and use a binding command (if you aren't familiar, it looks like <%# DataBinder.GetPropertyValue(Container.DataItem, "FieldName") %> in the markup -- see more details here). Then, in my RowUpdating event, I'd use e.Row.FindControl("controlName"), and update the Session data from that.

Honestly, if your back-end data isn't changing on a regular basis, I don't see any reason to programmatically create your GridViews. It over-complicates your C# code to go through these steps yourself when you can just set it up once in your markup. If you need to hide one GridView, you can always set its Visible property to false. Then, when you're ready to show it, set Visible = true.

Finally, I've spread my GridView code across so many events (button clicks, RowDataBound events from other GridViews/Repeaters, etc.), I can't imagine why someone would suggest that you only put it in Page_Load.

Best Answer

Related Solutions

.net – Why does GridView Rowupdating event not capture the new values of textbox

C# – GridView RowUpdating does not get the new values

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