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copied!<p>I am currently doing a project on web service for wine. I have the wine table with wineName and wineType. Also I have the search function implemented in the webservice coding as well as a separate webform to call the function of the search function</p> <p>I have the following code for performing search in the search service:</p> <pre><code><WebMethod()> _ Public Function Search(ByVal searchName As String) As System.Data.DataSet Dim connectionString As String = ConfigurationManager.ConnectionStrings("ConnectionString").ConnectionString Dim con As New SqlConnection(connectionString) Dim selectSql As String = "SELECT * From Wine WHERE WineType='" & searchName + "'" Dim selectAdapter As New Data.SqlClient.SqlDataAdapter(selectSql, con) Dim ds As New Data.DataSet con.Open() selectAdapter.Fill(ds, "Wine") con.Close() Return ds End Function </code></pre> <p>As for the webform, it's just a simple page with textbox labeled as searchName, a button and a gridView1 tied to ObjectDataSource.</p> <p>This is the coding i have for webform:</p> <pre><code>Partial Class Search Inherits System.Web.UI.Page Dim searching As searchwine.Service = New searchwine.Service Protected Sub Button1_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles Button1.Click If searchName.Text = "" Then lblDisplayError.Text = "Can't search empty field!" Else Dim ds As DataSet = searching.Search(searchName.Text) GridView1.DataSource = ds.Tables(0) GridView1.DataBind() GridView1.Visible = True lblDisplayError.Visible = False End If End Sub Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load lblDisplayError.Text = "" GridView1.Visible = False End Sub End Class </code></pre> <p>Everything seems fine, but i have the following error when i want to do a search:</p> <blockquote> <p>System.NullReferenceException: Object reference not set to an instance of an object. at Service.Search(String searchName)</p> </blockquote> <p>Can anyone help me out please?</p>

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