How to edit, update and delete in gridview when data comes from database?

This question can be ask here many time but my case is different. Please forgive me if i am wrong i have a page in which i have text-box and a button when i enter department name in text-box and press submit button my data store in the database

Now what i want is i want
(1) When i press submit button i can see that department in my grid-view.
(2) to show my department name in grid with edit and delete link so that when i click on edit link department name will pop in the department text-box and submit button become update button and when i make some changes and click on update button it will update and show it in the grid.

how can i do that This is my department page.cs code:

public partial class DepartmentMaster : System.Web.UI.Page
 {
SqlConnection con = new SqlConnection(ConfigurationManager.ConnectionStrings["WebGallery"].ToString());
SqlDataAdapter da; DataTable dt = new DataTable();
 DataSet ds = new DataSet();
protected void Page_Load(object sender, EventArgs e)
{ if (!IsPostBack)
{
con.Open();
da = new SqlDataAdapter("Select * from Department_Master", con); da.Fill(ds);
gvDepartment.DataSource = ds;
 gvDepartment.DataBind();
con.Close(); 
} 
}
 protected void btnSubmit_Click(object sender, EventArgs e)
 { using (SqlConnection con = new SqlConnection(ConfigurationManager.ConnectionStrings["MyGallery"].ToString()))
 {
con.Open(); string DepartmentName = tbDepartment.Text.Trim();
 using (SqlCommand cmd = con.CreateCommand())
{
cmd.CommandText = "insert into Department_Master(DepartmentName) values('" + DepartmentName + "')";
cmd.Parameters.AddWithValue("@DepartmentName", tbDepartment.Text.Trim());
cmd.ExecuteNonQuery();
}
con.Close();
tbDepartment.Text = "";
tbDepartment.Focus();
} 
}
}

Tags: C#, ASP.NET, Gridview, Buttons, Database Development