adminauthormanagement.aspx.cs

using System;
using System.Collections.Generic;
using System.Configuration;
using System.Data;
using System.Data.SqlClient;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;

namespace ELibraryManagement
{
    public partial class adminauthoramangement : System.Web.UI.Page
    {
        string strcon = ConfigurationManager.ConnectionStrings["con"].ConnectionString;
        protected void Page_Load(object sender, EventArgs e)
        {
            GridView1.DataBind();
        }
        //add button click
        protected void Button2_Click(object sender, EventArgs e)
        {
            if (checkIfAuthorExist())
            {
                Response.Write("<script>alert('Author with the same ID exist. Please try anyother authorID');</script>");
            }
            else
            {
                addNewAuthor();
            }
        }
        //update button click
        protected void Button3_Click(object sender, EventArgs e)
        {
            if (checkIfAuthorExist())
            {
                updateAuthor();
            }
            else
            {
                //addNewAuthor();
                
                Response.Write("<script>alert('Author Doesnot exist.');</script>");
            }
        }
        //delete button click
        protected void Button4_Click(object sender, EventArgs e)
        {
            if (checkIfAuthorExist())
            {
                deleteAuthor();
            }
            else
            {
                //addNewAuthor();

                Response.Write("<script>alert('Author Doesnot exist.');</script>");
            }
        }
        //GO button click
        protected void Button1_Click(object sender, EventArgs e)
        {
            getAuthorById();
        }

        //userdefinedFunction
        void getAuthorById()
        {
            try
            {
                SqlConnection con = new SqlConnection(strcon);
                if (con.State == System.Data.ConnectionState.Closed)
                {
                    con.Open();
                }
                SqlCommand cmd = new SqlCommand("Select * from author_master_tbl where author_id='" + TextBox1.Text.Trim() + "'", con);
                SqlDataAdapter da = new SqlDataAdapter(cmd);
                DataTable dt = new DataTable();
                da.Fill(dt);
                if (dt.Rows.Count >= 1)
                {
                    TextBox2.Text = dt.Rows[0][1].ToString();
                }
                else
                {
                    Response.Write("<script>alert('Invalid AuthorID');</script>");
                    clearForm();
                    GridView1.DataBind();
                }


            }
            catch (Exception ex)
            {
                Response.Write("<script>alert('" + ex.Message + "');</script>");
                
            }
        }
        void clearForm()
        {
            TextBox1.Text = "";
            TextBox2.Text = "";
        }
        void deleteAuthor()
        {
            try
            {
                SqlConnection con = new SqlConnection(strcon);
                if (con.State == System.Data.ConnectionState.Closed)
                {
                    con.Open();
                }
                SqlCommand cmd = new SqlCommand("DELETE from author_master_tbl WHERE author_id='" + TextBox1.Text.Trim() + "'", con);

                
               
                cmd.ExecuteNonQuery();
                con.Close();
                Response.Write("<script>alert('Author deleted successfully');</script>");
                clearForm();
                GridView1.DataBind();
            }
            catch (Exception ex)
            {
                Response.Write("<script>alert('" + ex.Message + "');</script>");
            }
        }
        void updateAuthor()
        {
            try
            {
                SqlConnection con = new SqlConnection(strcon);
                if (con.State == System.Data.ConnectionState.Closed)
                {
                    con.Open();
                }
                SqlCommand cmd = new SqlCommand("UPDATE author_master_tbl SET author_name=@author_name WHERE author_id='"+TextBox1.Text.Trim()+"'", con);

               
                cmd.Parameters.AddWithValue("@author_name", TextBox2.Text.Trim());
                cmd.ExecuteNonQuery();
                con.Close();
                Response.Write("<script>alert('Author updated successfully');</script>");
                clearForm();
                GridView1.DataBind();

            }
            catch (Exception ex)
            {
                Response.Write("<script>alert('" + ex.Message + "');</script>");
            }
        }
        void addNewAuthor()
        {
            try
            {
                SqlConnection con = new SqlConnection(strcon);
                if (con.State == System.Data.ConnectionState.Closed)
                {
                    con.Open();
                }
                SqlCommand cmd = new SqlCommand("INSERT INTO author_master_tbl(author_id,author_name) values" +
                    "(@author_id,@author_name)", con);

                cmd.Parameters.AddWithValue("@author_id", TextBox1.Text.Trim());
                cmd.Parameters.AddWithValue("@author_name", TextBox2.Text.Trim());
                cmd.ExecuteNonQuery();
                con.Close();
                Response.Write("<script>alert('Author added successfully');</script>");
                clearForm();
                GridView1.DataBind();

            }
            catch (Exception ex)
            {
                Response.Write("<script>alert('" + ex.Message + "');</script>");
            }
        }
        bool checkIfAuthorExist()
        {
            try
            {
                SqlConnection con = new SqlConnection(strcon);
                if (con.State == System.Data.ConnectionState.Closed)
                {
                    con.Open();
                }
                SqlCommand cmd = new SqlCommand("Select * from author_master_tbl where author_id='" + TextBox1.Text.Trim() + "'", con);
                SqlDataAdapter da = new SqlDataAdapter(cmd);
                DataTable dt = new DataTable();
                da.Fill(dt);
                if (dt.Rows.Count >= 1)
                {
                    return true;
                }
                else
                {
                    return false;
                }


            }
            catch (Exception ex)
            {
                Response.Write("<script>alert('" + ex.Message + "');</script>");
                return false;
            }
        }
    }
}