Thursday, 2 January 2014

Distinct values in datatable c# / vb.net

Posted on 21:23 in ,
Intoduction:
This article is helps get distinct values from database in datatable formats using asp.net. Page load events bind the gridview before get distinct values. After bind the gridview distinct records of subject columns name only.
Designing Page (Source view):
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head id="Head1" runat="server">
<title> Distinct values in datatable c# / vb.net using ASP.NET</title>
</head>
<body>
<form id="form1" runat="server">
<div>
<asp:Button ID="btnDistinctValues" runat="server" OnClick="btnDistinctValues_Click" Text="Distinct values in Datatable" />
<br />
<br />
<asp:GridView ID="grvOutput" runat="server" AutoGenerateColumns="true">
</asp:GridView>
</div>
</form>
</body>
</html>
VB.NET:
Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
        If Not Page.IsPostBack Then
            Dim dtTemp As New DataTable
            Dim con As New SqlConnection("server=vignesh;uid=sa;pwd=sa123;database=asp_dotnet")
            con.Open()
            Dim cmd As New SqlCommand("SELECT * FROM studentmarkdetails", con)
            Dim da As New SqlDataAdapter(cmd)
            da.Fill(dtTemp)
            con.Close()
            ViewState("StudentInformation") = dtTemp
            grvOutput.DataSource = dtTemp
            grvOutput.DataBind()
        End If
End Sub
Protected Sub btnDistinctValues_Click(ByVal sender As Object, ByVal e As System.EventArgs)
        Dim dtTemp As DataTable = ViewState("StudentInformation")
        Dim dtDistinctRecords As DataTable = dtTemp.DefaultView.ToTable(True, "subject")
 grvOutput.DataSource = dtDistinctRecords
        grvOutput.DataBind()
End Sub
C#.NET:
protected void Page_Load(object sender, EventArgs e)
        {
            if (!Page.IsPostBack)
            {
                DataTable dtTemp = new DataTable();
                SqlConnection con = new SqlConnection("server=vignesh;uid=sa;pwd=sa123;database=asp_dotnet");
                con.Open();
                SqlCommand cmd = new SqlCommand("SELECT * FROM studentmarkdetails", con);
                SqlDataAdapter da = new SqlDataAdapter(cmd);
                da.Fill(dtTemp);
                con.Close();
                ViewState["StudentInformation"] = dtTemp;
                grvOutput.DataSource = dtTemp;
                grvOutput.DataBind();
            }
        }
protected void btnDistinctValues_Click(object sender, EventArgs e)
        {
            DataTable dtTemp = (DataTable)ViewState["StudentInformation"];
            DataTable dtDistinctRecords = dtTemp.DefaultView.ToTable(true, "subject");
     grvOutput.DataSource = dtDistinctRecords;
            grvOutput.DataBind();
        }
Demo:


0 comments:

Post a Comment