Web Development

using System;
using System.Collections;
using System.Configuration;
using System.Data;
using System.Linq;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.HtmlControls;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Xml.Linq;

public partial class _Default : System.Web.UI.Page
{
    ClsMngr obj = new ClsMngr();
    ClsUsers objUsers = new ClsUsers();
    public static int numberDiv;
    private int TotalRecords = 0;
    private int TotalPages = 0;
    private int PageSize = 0;
    private int CurrentPage = 0;

    protected void Page_Load(object sender, EventArgs e)
    {
        dataGrid.PagerStyle.Mode = PagerMode.NumericPages;
        if (!IsPostBack)
        {
            fillDataGrid();
        }

    }

    protected void dataGrid_Edit(object source, DataGridCommandEventArgs e)
    {
        dataGrid.EditItemIndex = e.Item.ItemIndex;
        fillDataGrid();
    }

    protected void dataGrid_Update(object source, DataGridCommandEventArgs e)
    {
        objUsers.Action = "update";
        objUsers.UserId = Convert.ToInt32(e.Item.Cells[0].Text);
        objUsers.UserName = ((TextBox)e.Item.Cells[1].Controls[0]).Text;
        objUsers.GroupId = Convert.ToInt32(((DropDownList)e.Item.Cells[2].Controls[0].FindControl("ddlGroup")).Text);
        obj.Users(objUsers);
        Response.Redirect("DataGrid.aspx");
    }

    protected void dataGrid_Cancel(object source, DataGridCommandEventArgs e)
    {
        dataGrid.EditItemIndex = -1;
        fillDataGrid();
    }

    protected void dataGrid_Delete(object source, DataGridCommandEventArgs e)
    {
        objUsers.Action = "delete";
        objUsers.UserId = Convert.ToInt32(e.Item.Cells[0].Text);
        obj.Users(objUsers);
        Response.Redirect("DataGrid.aspx");
    }

    protected void dataGrid_ItemDataBound(object sender, DataGridItemEventArgs e)
    {
        object objGroupId = DataBinder.Eval(e.Item.DataItem, "User_GroupId");
        if (e.Item.ItemType == System.Web.UI.WebControls.ListItemType.Item ||
            e.Item.ItemType == System.Web.UI.WebControls.ListItemType.AlternatingItem)
        {
            e.Item.Cells[2].Text = GetGroupName(Convert.ToInt32(objGroupId));
        }
        if (e.Item.ItemType == System.Web.UI.WebControls.ListItemType.EditItem)
        {
            ClsGroups objGroups = new ClsGroups();
            objGroups.Action = "select";
            objGroups.GroupIdFlag = 1;
            objGroups.NameEngFlag = 1;
            DataTable dtGroup = obj.Groups(objGroups);
            ((DropDownList)e.Item.FindControl("ddlGroup")).DataSource = dtGroup;
            ((DropDownList)e.Item.FindControl("ddlGroup")).DataValueField = "Group_GroupId";
            ((DropDownList)e.Item.FindControl("ddlGroup")).DataTextField = "Group_NameEng";
            ((DropDownList)e.Item.FindControl("ddlGroup")).SelectedValue = objGroupId.ToString(); 
            ((DropDownList)e.Item.FindControl("ddlGroup")).DataBind();
        }
    }

    private string GetGroupName(int intGroupId)
    {
        ClsGroups objGroups = new ClsGroups();
        objGroups.Action = "select";
        objGroups.GroupId = intGroupId;
        objGroups.GroupIdFlag = 1;
        objGroups.NameEngFlag = 1;
        DataTable dtGroup = obj.Groups(objGroups);
        if (dtGroup.Rows.Count == 0) return "";
        return dtGroup.Rows[0]["Group_NameEng"].ToString();
    }

    protected void Pager(object source, DataGridPageChangedEventArgs e)
    {
        dataGrid.CurrentPageIndex = e.NewPageIndex;
        fillDataGrid();
    }

    protected void NavigationLink_Click(object source, CommandEventArgs e)
    {
        int RecordCount;
        DataTable dSet = null;
        dSet = (DataTable)Cache["AllRecords"];
        PageSize = dataGrid.PageSize;
        switch (e.CommandName)
        {
            case "First":
                ViewState["CurrentPage"] = 0;
                dataGrid.CurrentPageIndex = 0;
                dataGrid.DataSource = dSet;
                dataGrid.DataBind();
                PreviousPage.Enabled = false;
                NextPage.Enabled = true;
                FirstPage.Enabled = false;
                LastPage.Enabled = true;
                TotalRecords = (int)ViewState["TotalRecords"];
                lblPageDetails.Text = "1 - " + PageSize.ToString() + " of " + TotalRecords.ToString();
                break;
            case "Last":
                TotalPages = (int)ViewState["TotalPages"];
                ViewState["CurrentPage"] = TotalPages - 1;
                dataGrid.CurrentPageIndex = TotalPages - 1; //since page number starts from 0
                dataGrid.DataSource = dSet;
                dataGrid.DataBind();
                NextPage.Enabled = false;
                PreviousPage.Enabled = true;
                LastPage.Enabled = false;
                FirstPage.Enabled = true;
                RecordCount = (TotalPages - 1) * PageSize;
                TotalRecords = (int)ViewState["TotalRecords"];
                lblPageDetails.Text = (RecordCount + 1).ToString() + " - " + TotalRecords.ToString() + " of " + TotalRecords.ToString();
                break;
            case "Next":
                CurrentPage = (int)ViewState["CurrentPage"];
                CurrentPage = CurrentPage + 1;
                ViewState["CurrentPage"] = CurrentPage;
                dataGrid.CurrentPageIndex = CurrentPage;
                dataGrid.DataSource = dSet;
                dataGrid.DataBind();
                RecordCount = CurrentPage * PageSize;
                TotalRecords = (int)ViewState["TotalRecords"];
                if (CurrentPage == dataGrid.PageCount - 1)
                {
                    NextPage.Enabled = false;
                    PreviousPage.Enabled = true;
                    LastPage.Enabled = false;
                    FirstPage.Enabled = true;
                    lblPageDetails.Text = (RecordCount + 1).ToString() + " - " + TotalRecords.ToString() + " of " + TotalRecords.ToString();
                }
                else
                {
                    NextPage.Enabled = true;
                    PreviousPage.Enabled = true;
                    LastPage.Enabled = true;
                    FirstPage.Enabled = true;
                    lblPageDetails.Text = (RecordCount + 1).ToString() + " - " + (RecordCount + PageSize).ToString() + " of " + TotalRecords.ToString();
                }
                break;
            case "Prev":
                CurrentPage = (int)ViewState["CurrentPage"];
                CurrentPage = CurrentPage - 1;
                ViewState["CurrentPage"] = CurrentPage;
                dataGrid.CurrentPageIndex = CurrentPage;
                dataGrid.DataSource = dSet;
                dataGrid.DataBind();
                RecordCount = CurrentPage * PageSize;
                TotalRecords = (int)ViewState["TotalRecords"];
                if (CurrentPage == 0)
                {
                    PreviousPage.Enabled = false;
                    NextPage.Enabled = true;
                    FirstPage.Enabled = false;
                    LastPage.Enabled = true;
                    lblPageDetails.Text = "1 - " + PageSize.ToString() + " of " + TotalRecords.ToString();
                }
                else
                {
                    NextPage.Enabled = true;
                    PreviousPage.Enabled = true;
                    LastPage.Enabled = true;
                    FirstPage.Enabled = true;
                    lblPageDetails.Text = (RecordCount + 1).ToString() + " - " + (RecordCount + PageSize).ToString() + " of " + TotalRecords.ToString();
                }
                break;
        }

    }

    protected void onSort(object source, DataGridSortCommandEventArgs e)
    {
        objUsers.Action = "select";
        DataTable dtUsers = obj.Users(objUsers);
        if (dtUsers != null)
        {
            DataView dataView = new DataView(dtUsers);
            if ((numberDiv % 2) == 0)
                dataView.Sort = e.SortExpression + " " + "ASC";
            else dataView.Sort = e.SortExpression + " " + "DESC";
            numberDiv++;
            dataGrid.DataSource = dataView;
            dataGrid.DataBind();
        }
    }

    private void fillDataGrid()
    {
        objUsers.Action = "select";
        DataTable dtUsers = obj.Users(objUsers);
        Cache["AllRecords"] = dtUsers;
        DataTable dtUsersNew = new DataTable();
        dtUsersNew = (DataTable)Cache["AllRecords"];
        ViewState["TotalRecords"] = dtUsersNew.Rows.Count;
        dataGrid.CurrentPageIndex = 0;
        dataGrid.DataSource = dtUsersNew;
        dataGrid.DataBind();
        TotalRecords = (int)ViewState["TotalRecords"];
        ViewState["TotalPages"] = dataGrid.PageCount;
        ViewState["CurrentPage"] = 0;
        PreviousPage.Enabled = false;
        NextPage.Enabled = true;
        FirstPage.Enabled = false;
        LastPage.Enabled = true;
        if (TotalRecords == 0)
        {
            dataGrid.Visible = false;
            Panel1.Visible = false;
        }
        else if (TotalRecords <= dataGrid.PageSize)
        {
            dataGrid.Visible = true;
            Panel1.Visible = true; 
            lblPageDetails.Text = "1 - " + TotalRecords.ToString() + " of " + TotalRecords.ToString();
            NextPage.Enabled = false;
            LastPage.Enabled = false;
        }
        else
        {
            dataGrid.Visible = true;
            Panel1.Visible = true;
           lblPageDetails.Text = "1 - " + dataGrid.PageSize.ToString() + " of " + TotalRecords.ToString();
        }
    }
}