Cannot edit null values in ASP.NET Gridview
<p>I have searched this forum and it seems that there is no other threat about my problem.</p>

<p>Well I have a gridview that has a number of fields. Some of them are NULL.</p>

<p>If I press edit and edit a field that is NOT NULL and press save then the information is correctly altered. If I choose a field that is NULL then,</p>

<p>NO information is saved.</p>

<p>I will include some of my SQL query and the piece of the code that does the problem.</p>

<p>Please if you know I will apriciate your help</p>

<p>SQL Query </p>

<pre><code>   SELECT Request.column1,
    Request.column2, 
    Request.column3,
    Request.column4, 
    column5= isnull(Request.column5,'Select Date')
    FROM Reques
</code></pre>

<p>ASP Code for Column 5 that is the only one that has null fields and does the problem</p>

<pre><code> &lt;asp:TemplateField HeaderText="Column 5" SortExpression="column5"&gt;
                    &lt;EditItemTemplate&gt;
                  &lt;asp:DropDownList ID="DropDownList1" runat="server" DataSourceID="SqlDataSource1"
                            DataTextField="column5" DataValueField="column5" AppendDataBoundItems="true" 
                                                        SelectedValue='&lt;%# Eval("column5") %&gt;'&gt;

                        &lt;/asp:DropDownList&gt;  
                    &lt;/EditItemTemplate&gt;
                    &lt;ItemTemplate&gt;
                        &lt;asp:Label ID="Label1" runat="server" Text='&lt;%# Eval("column5") %&gt;'&gt;&lt;/asp:Label&gt;
                    &lt;/ItemTemplate&gt;
                &lt;/asp:TemplateField&gt;
</code></pre>
