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POUpdate Gridview using OnClick Event
 

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    <p>I'm developing a basic web form that allows users to search certain columns in a database and display those records in a GridView. I have several TextBox controls that allow users to search for a name, id, etc. I am using LinqToSql for my data access layer. It's your basic search form.</p> <p>The trouble comes with the GridView I am attempting to use display the data. I have the query itself in the OnClick event method of a Button control.</p> <pre><code>protected void SearchSpecific_Click(object sender, EventArgs e) { MyDataContext dbContext = new MyDataContext(); var results = from row in dbContext.MyTable select row; if(TextBoxIsValid(IDNumber)) results = results.Where(m =&gt; m.ID == Int32.Parse(IDNumber.Text)); if (validationFlag) { // this part doesn't seem right SearchResultDataset.DataSource = results; SearchResultDataset.DataBind(); } } </code></pre> <p>Here's the gridview, though it's nothing special:</p> <pre><code>&lt;asp:GridView ID="SearchResultDataset" runat="server" AlternatingRowStyle-CssClass="alt" CssClass="search_results" GridLines="None" AutoGenerateColumns="true"&gt;&lt;/asp:GridView&gt; </code></pre> <p>Everything runs smoothly until I get to the DataBind() method and a NullReferenceException was thrown. Holy exceptions, Batman!</p> <p>The debugger tells me that results has the correct values, but I have a feeling it has to do with binding datasources on postback. I feel like I'm missed something... Any suggestions? I can provide a stack trace if necessary.</p> <p><strong>EDIT:</strong></p> <p>There's a much larger problem at hand. I've tried adding both a LinqDataSource and an ObjectDataSource control to my page and both throw a NullReferenceException. I constructed both using the GUI and they look perfect.</p> <p>After this I then assigned a DataSource in the Page_Load method:</p> <pre><code>try { MyDataContext dbc = new MyDataContext(); SearchResultDataset.DataSource = dbc.MyTable; SearchResultDataset.DataBind(); } catch (Exception ex) { errText.InnerHtml = ex.ToString(); } </code></pre> <p>Came up with this exception:</p> <pre><code>System.Reflection.TargetInvocationException: Property accessor 'IsPostBack' on object 'MySite.MySite' threw the following exception:'Object reference not set to an instance of an object.' ---&gt; System.NullReferenceException: Object reference not set to an instance of an object. </code></pre> <p>at System.Web.UI.UserControl.get_IsPostBack()</p> <p>The exception is definitely being thrown in the DataBind() method. This raises the question WTF is going on? I can't seem to be able to bind a linqtosql source to my GridView. I can't seem to find the page, but I read somewhere that GridView has difficulty binding to anything that isn't a DataSet object.</p> <p><strong>UPDATE</strong></p> <p>Used SqlDataSource control to access database.</p>
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