ASP.NET

string constr = "Data Source=MAINSERVER;Initial Catalog=Inventory;User ID=sa;Password=nsg_ss_0103";<br />
    protected void Page_Load(object sender, EventArgs e)<br />
    {<br />
        <br />
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        if (Page.IsPostBack == false)<br />
        {<br />
            GridView1.PageIndex = 0;<br />
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            bindata();<br />
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        }<br />
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    }<br />
private void bindata()<br />
    {<br />
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        SqlConnection con12 = new SqlConnection(constr);<br />
        SqlDataAdapter da12 = new SqlDataAdapter("SELECT [CategoryNameE], [ItemKey], [ItemKeyNameE], [CurrentQTY], [SalesPrice] FROM [CurrentInWH]", con12);<br />
        DataSet ds = new DataSet();<br />
        da12.Fill(ds, "t");<br />
        GridView1.DataSource = ds.Tables["t"];<br />
        GridView1.DataBind();<br />
    }<br />
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 private void GetGridViewData()<br />
    {<br />
        DataTable dt;<br />
        if(Session["CheckedRecords"]!=null)<br />
        //if (ViewState["CheckedRecords"] != null)<br />
            dt = (DataTable)Session["CheckedRecords"];<br />
        else<br />
            dt = CreateNewTable();<br />
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        for (int i = 0; i < GridView1.Rows.Count; i++)<br />
        {<br />
            CheckBox chk = (CheckBox)GridView1.Rows[i].Cells[0].FindControl("chk");<br />
            if (chk.Checked)<br />
            {<br />
                dt = AddNewRow(GridView1.Rows[i], dt);<br />
            }<br />
            else<br />
            {<br />
                dt = RemoveRow(GridView1.Rows[i], dt);<br />
            }<br />
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        }<br />
        Session["CheckedRecords"] = dt;<br />
        <br />
    }<br />
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 private DataTable CreateNewTable()<br />
    {<br />
        DataTable dt = new DataTable();<br />
        dt.Columns.Add("CategoryNameE");<br />
        dt.Columns.Add("ItemKey");<br />
        dt.Columns.Add("ItemKeyNameE");<br />
        dt.Columns.Add("CurrentQTY");<br />
        dt.Columns.Add("SalesPrice");<br />
        dt.Columns.Add("Quantity");<br />
        dt.Columns.Add("Total");<br />
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        dt.AcceptChanges();<br />
        return dt;<br />
    }<br />
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private DataTable AddNewRow(GridViewRow gvrow, DataTable dt)<br />
    {<br />
        DataRow[] dr = dt.Select("ItemKey = '" + gvrow.Cells[2].Text + "'");<br />
        if (dr.Length <= 0)<br />
        {<br />
            dt.Rows.Add();<br />
            dt.Rows[dt.Rows.Count - 1]["CategoryNameE"] = gvrow.Cells[1].Text;<br />
            dt.Rows[dt.Rows.Count - 1]["ItemKey"] = gvrow.Cells[2].Text;<br />
            dt.Rows[dt.Rows.Count - 1]["ItemKeyNameE"] = gvrow.Cells[3].Text;<br />
            dt.Rows[dt.Rows.Count - 1]["CurrentQTY"] = gvrow.Cells[4].Text;<br />
            dt.Rows[dt.Rows.Count - 1]["SalesPrice"] = gvrow.Cells[5].Text;<br />
            dt.Rows[dt.Rows.Count - 1]["Quantity"] = gvrow.Cells[6].Text;<br />
            dt.Rows[dt.Rows.Count - 1]["Total"] = gvrow.Cells[7].Text;<br />
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            dt.AcceptChanges();<br />
        }<br />
        return dt;<br />
    }<br />
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private DataTable RemoveRow(GridViewRow gvrow, DataTable dt)<br />
    {<br />
        DataRow[] dr = dt.Select("ItemKey= '" + gvrow.Cells[2].Text + "'");<br />
        if (dr.Length > 0)<br />
        {<br />
            dt.Rows.Remove(dr[0]);<br />
            dt.AcceptChanges();<br />
        }<br />
        return dt;<br />
    }<br />
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protected void chk_CheckedChanged(object sender, EventArgs e)<br />
    {<br />
        GetGridViewData();<br />
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        TextBox txtqty1; TextBox txttott; CheckBox ch = null;<br />
        for (int i = 0; i < GridView1.Rows.Count; i++)<br />
        {<br />
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            txtqty1 = (TextBox)GridView1.Rows[i].FindControl("txtqty");<br />
            txttott = (TextBox)GridView1.Rows[i].FindControl("txttot");<br />
            ch = (CheckBox)GridView1.Rows[i].FindControl("chk");<br />
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            if (ch.Checked)<br />
            {<br />
                txtqty1.Visible = true;<br />
                txttott.Visible = true;<br />
            }<br />
            else<br />
            {<br />
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                txtqty1.Visible = false;<br />
                txttott.Visible = false;<br />
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            }<br />
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        }<br />
        <br />
    }<br />
// in second page<br />
DataTable dt = (DataTable)Session["CheckedRecords"];<br />
GridView1.DataSource = dt;<br />
        GridView1.DataBind();<br />
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