Add, Update and Delete List Items Programmatically in Sharepoint

using System;
using System.ComponentModel;
using System.Web.UI.WebControls.WebParts;
using Microsoft.SharePoint;
using Microsoft.SharePoint.Utilities;
using System.Data;
using System.Web.UI.WebControls;
namespace payrollwp1.AddDepartment
{
    [ToolboxItemAttribute(false)]
    public partial class AddDepartment: WebPart
    {
        SPSite site = new SPSite(SPContext.Current.Web.Url);
        SPWeb sweb;
        // Uncomment the following SecurityPermission attribute only when doing Performance Profiling on a farm solution
        // using the Instrumentation method, and then remove the SecurityPermission attribute when the code is ready
        // for production. Because the SecurityPermission attribute bypasses the security check for callers of
        // your constructor, it’s not recommended for production purposes.
        // [System.Security.Permissions.SecurityPermission(System.Security.Permissions.SecurityAction.Assert, UnmanagedCode = true)]
        public AddDepartment() {}

        protected override void OnInit(EventArgs e)
        {
            base.OnInit(e);
            InitializeControl();
        }

        protected void Page_Load(object sender, EventArgs e)
        {
            if (!Page.IsPostBack)
            {
                lblMsg.Text = “”;
                LoadData();

            }
        }
        void LoadData()
        {
            DataTable dt = new DataTable();
            try
            {
                sweb = site.OpenWeb();
                SPList slist = sweb.Lists[“Department List”];
                SPListItemCollection coll = slist.GetItems();
                dt = coll.GetDataTable();
                GridView1.DataSource = dt;
                GridView1.DataBind();
            } catch (Exception ex) {
                lblMsg.Text = ex.Message;
            }
        }

        protected void btnSubmit_Click(object sender, EventArgs e)
        {
            try
            {
                sweb = site.OpenWeb();
                sweb.AllowUnsafeUpdates = true;
                SPList slist = sweb.Lists[“Department List”];
                if (btnSubmit.Text == “Submit”)
                {
                    SPListItem sitem = slist.Items.Add();
                    sitem[“Title”] = txtTitle.Text;
                    sitem[“Department Name”] = txtDeptName.Text;
                    sitem[“Description”] = txtDesc.Text;
                    sitem.Update();
                    LoadData();
                    lblMsg.Text = “Department Added Successfully”;

                }
                else if (btnSubmit.Text == “Update”)
                {
                    SPListItem obj = slist.GetItemById(Convert.ToInt32(hdfSl_no.Value));
                    obj[“Title”] = txtTitle.Text;
                    obj[“Department Name”] = txtDeptName.Text;
                    obj[“Description”] = txtDesc.Text.Trim();
                    obj.Update();
                    LoadData();
                    lblMsg.Text = “Department Update Successfully”;
                }
                sweb.AllowUnsafeUpdates = false;
            }
            catch (Exception ex)
            {
                lblMsg.Text = ex.Message;
            }
        }

        protected void GridView1_RowCommand(object sender, System.Web.UI.WebControls.GridViewCommandEventArgs e) {
            if (e.CommandName == “cmdEditDept”)
            {
                int rowindex = Convert.ToInt32(e.CommandArgument);

                Label title = (Label) GridView1.Rows[rowindex].Cells[1].FindControl(“lbl_sl”);
                Label dept = (Label) GridView1.Rows[rowindex].Cells[2].FindControl(“lbl_dept”);
                Label desc = (Label) GridView1.Rows[rowindex].Cells[3].FindControl(“lbl_status”);
                txtTitle.Text = title.Text;
                txtDeptName.Text = dept.Text;
                txtDesc.Text = desc.Text;
                hdfSl_no.Value = ((HiddenField) GridView1.Rows[rowindex].FindControl(“HiddenField1″)).Value;
                btnSubmit.Text = “Update”;

            }
            if (e.CommandName == “cmdDeleteDept”)
            {
                sweb = site.OpenWeb();
                SPList slist = sweb.Lists[“Department List”];
                int rowindex = Convert.ToInt32(e.CommandArgument);
                HiddenField sl = ((HiddenField) GridView1.Rows[rowindex].FindControl(“HiddenField1″));
                slist.GetItemById(Convert.ToInt32(sl.Value)).Delete();
                LoadData();
                lblMsg.Text = “Department Deleted Successfully”;
            }
        }

        protected void btnReset_Click(object sender, EventArgs e)
        {
            txtDesc.Text = “”;
            txtTitle.Text = “”;
            txtDeptName.Text = “”;
            btnSubmit.Text = “Submit”;
        }
    }
}