Author: coder

Connection to MySql

Posted on by coder 
   

using System;
using System.Data;
using ByteFX.Data.MySqlClient;

   class MySqlConnect
   {
      static void Main() 
      {
         string connString = @"Data Source=server;Database=mydb;User ID=username;Password=pwd;Command Logging=false";
         MySqlConnection conn = new MySqlConnection(connString);

         try 
         {
            conn.Open();
            Console.WriteLine("Connection opened.");

            Console.WriteLine("Connection Properties:");   
            Console.WriteLine("	Connection String: {0}",conn.ConnectionString);    
            Console.WriteLine("	Database: {0}",conn.Database);   
            Console.WriteLine("	ServerVersion: {0}",
               conn.ServerVersion);
            Console.WriteLine(
               "	State: {0}",
               conn.State);
         } 
         catch (MySqlException e) 
         {
            Console.WriteLine("Error: " + e);  
         }
         finally 
         {
            conn.Close();
            Console.WriteLine("Connection closed.");
         }
      }
   }

Deal with the many to many relation

Posted on by coder 
   

using System;
using System.Data;            // use ADO.NET namespace
using System.Data.SqlClient;  // use SQL Server provider

class DataRelationExample
{
   public static void Main() 
   {
      SqlConnection thisConnection = new SqlConnection("server=(local)SQLEXPRESS;database=MyDatabase;Integrated Security=SSPI");

      SqlDataAdapter thisAdapter = new SqlDataAdapter("SELECT CustomerID, CompanyName FROM Customers", thisConnection);

      SqlCommandBuilder thisBuilder = new SqlCommandBuilder(thisAdapter);

      DataSet thisDataSet = new DataSet();

      SqlDataAdapter custAdapter = new SqlDataAdapter("SELECT * FROM Customers", thisConnection);
      SqlDataAdapter orderAdapter = new SqlDataAdapter("SELECT * FROM Orders", thisConnection);
      custAdapter.Fill(thisDataSet, "Customers");
      orderAdapter.Fill(thisDataSet, "Orders");

      DataRelation custOrderRel = thisDataSet.Relations.Add("CustOrders",
         thisDataSet.Tables["Customers"].Columns["CustomerID"],
         thisDataSet.Tables["Orders"].Columns["CustomerID"]);
         
      foreach (DataRow custRow in thisDataSet.Tables["Customers"].Rows)
      {
         Console.WriteLine("Customer ID: " + custRow["CustomerID"] + " Name: " + custRow["CompanyName"]);
         foreach (DataRow orderRow in custRow.GetChildRows(custOrderRel)) {
            Console.WriteLine("  Order ID: " + orderRow["OrderID"]);
         }
      }
      

      custOrderRel.Nested = true;

      thisDataSet.WriteXml(@"nwinddata.xml");
      Console.WriteLine(@"Successfully wrote XML output to file nwinddata.xml");

   }
}

Read image data from database and display that image

Posted on by coder 
   

using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;
using System.Data;
using System.Data.SqlClient;
using System.IO;
 
 
public class Form1 : System.Windows.Forms.Form {
   private System.Windows.Forms.Button button1;
   private System.Windows.Forms.TextBox textBox1;
   private System.Windows.Forms.PictureBox pictureBox1;
   private Images images;

   private System.ComponentModel.Container components = null;

   public Form1() {
      InitializeComponent();

      images = new Images();

      if (images.GetRow()) {
            this.textBox1.Text = images.GetFilename();
            this.pictureBox1.Image = (Image)images.GetImage();
      } else {
            this.textBox1.Text = "DONE";
            this.pictureBox1.Image = null;
      }
   }

   private void InitializeComponent() {
      this.button1 = new System.Windows.Forms.Button();
      this.textBox1 = new System.Windows.Forms.TextBox();
      this.pictureBox1 = new System.Windows.Forms.PictureBox();
      this.SuspendLayout();

      this.button1.Location = new System.Drawing.Point(200, 8);
      this.button1.Name = "button1";
      this.button1.TabIndex = 0;
      this.button1.Text = "Next";
      this.button1.Click += new System.EventHandler(this.button1_Click);

      this.textBox1.Location = new System.Drawing.Point(24, 8);
      this.textBox1.Name = "textBox1";
      this.textBox1.Size = new System.Drawing.Size(144, 20);
      this.textBox1.TabIndex = 1;
      this.textBox1.Text = "";

      this.pictureBox1.Location = new System.Drawing.Point(8, 48);
      this.pictureBox1.Name = "pictureBox1";
      this.pictureBox1.Size = new System.Drawing.Size(280, 208);
      this.pictureBox1.TabIndex = 2;
      this.pictureBox1.TabStop = false;

      this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
      this.ClientSize = new System.Drawing.Size(292, 272);
      this.Controls.Add(this.pictureBox1);
      this.Controls.Add(this.textBox1);
      this.Controls.Add(this.button1);
      this.Name = "Form1";
      this.Text = "Display Images";
      this.ResumeLayout(false);
   }

   static void Main() {
      Application.Run(new Form1());
   }

   private void button1_Click(object sender, System.EventArgs e) {
      if (images.GetRow()) {
         this.textBox1.Text = images.GetFilename();
         this.pictureBox1.Image = (Image)images.GetImage();
      } else {
         this.textBox1.Text = "DONE";
         this.pictureBox1.Image = null;
      }
   }
}


public class Images{
   string imageFilename = null;
   byte[] imageBytes = null;

   SqlConnection imageConnection = null;
   SqlCommand imageCommand = null;
   SqlDataReader imageReader = null;

   public Images() {
      imageConnection = new SqlConnection("server=(local)SQLEXPRESS;database=MyDatabase;Integrated Security=SSPI");
      imageCommand = new SqlCommand(@"select imagefile, imagedata from imagetable", imageConnection);

      imageConnection.Open();
      imageReader = imageCommand.ExecuteReader();
   }

   public Bitmap GetImage() {
      MemoryStream ms = new MemoryStream(imageBytes);
      Bitmap bmap = new Bitmap(ms);

      return bmap;
   }

   public string GetFilename() {
      return imageFilename;
   }

   public bool GetRow() {
      if (imageReader.Read()) {
        imageFilename = (string) imageReader.GetValue(0);
        imageBytes = (byte[]) imageReader.GetValue(1);
        return true;
      }else {
        return false;
      }
   }

   public void EndImages() {
      imageReader.Close();
      imageConnection.Close();
   }
}

Insert Data Using SqlCommandBuilder

Posted on by coder 
   


/*
 * C# Programmers Pocket Consultant
 * Author: Gregory S. MacBeth
 * Email: gmacbeth@comporium.net
 * Create Date: June 27, 2003
 * Last Modified Date:
 * Version: 1
 */
using System;
using System.Data;
using System.Data.SqlClient;

namespace Client.Chapter_13___ADO.NET
{
    public class InsertingDataUsingCommandBuilder
    {
        static void Main(string[] args)
        {
            SqlConnection MyConnection = new SqlConnection(@"Data Source=(local); Initial Catalog = CaseManager; Integrated Security=true");
            SqlDataAdapter MyDataAdapter = new SqlDataAdapter("SELECT ID, Contact, Email FROM Test", MyConnection);
            SqlCommandBuilder MyCmd = new SqlCommandBuilder(MyDataAdapter);
            DataSet MyDataSet = new DataSet();

            MyDataAdapter.Fill(MyDataSet);

            DataRow MyRow = MyDataSet.Tables[0].NewRow();

            MyRow["ID"] = 200;
            MyRow["Contact"] = "Greg";
            MyRow["Email"] = "MacBeth";
            MyDataSet.Tables[0].Rows.Add(MyRow);
            MyDataAdapter.Update(MyDataSet);
        }
    }
}

Inserte Data Using SQL Statements

Posted on by coder 
   


/*
 * C# Programmers Pocket Consultant
 * Author: Gregory S. MacBeth
 * Email: gmacbeth@comporium.net
 * Create Date: June 27, 2003
 * Last Modified Date:
 * Version: 1
 */
using System;
using System.Data;
using System.Data.SqlClient;

namespace Client.Chapter_13___ADO.NET
{
    
    public class InsertingDataUsingSQLStatements
    {
        static void Main(string[] args)
        {
            SqlConnection MyConnection = new SqlConnection(@"Data Source=(local); Initial Catalog = CaseManager; Integrated Security=true");

            MyConnection.Open();

            String MyString = @"INSERT INTO Test(ID, Contact, Email) VALUES(2, 'Greg', 'MacBeth')";
            SqlCommand MyCmd = new SqlCommand(MyString, MyConnection);

            MyCmd.ExecuteScalar();
            MyConnection.Close();
        }
    }
}

Run an INSERT statement with parameters

Posted on by coder 
   
 

using System;
using System.Data;
using System.Data.SqlClient;

class UsingParameters {
    public static void Main() {
        SqlConnection mySqlConnection = new SqlConnection("server=localhost;database=Northwind;uid=sa;pwd=sa");
        mySqlConnection.Open();
        SqlCommand mySqlCommand = mySqlConnection.CreateCommand();
        mySqlCommand.CommandText =
          "INSERT INTO Customers (" +
          "  CustomerID, CompanyName, ContactName" +
          ") VALUES (" +
          "  @CustomerID, @CompanyName, @ContactName" +
          ")";
        mySqlCommand.Parameters.Add("@CustomerID", SqlDbType.NChar, 5);
        mySqlCommand.Parameters.Add("@CompanyName", SqlDbType.NVarChar, 40);
        mySqlCommand.Parameters.Add("@ContactName", SqlDbType.NVarChar, 30);
        mySqlCommand.Parameters["@CustomerID"].Value = "J4COM";
        mySqlCommand.Parameters["@CompanyName"].Value = "J4 Company";
        mySqlCommand.Parameters["@ContactName"].IsNullable = true;
        mySqlCommand.Parameters["@ContactName"].Value = DBNull.Value;
        mySqlCommand.ExecuteNonQuery();
        Console.WriteLine("Successfully added row to Customers table");

        mySqlConnection.Close();
    }
}

Bind parameters to insert command

Posted on by coder 
   


using System;
using System.Data;
using System.Data.SqlClient;

   class PropagateAdds{
      static void Main() {
         string connString = "server=(local)SQLEXPRESS;database=MyDatabase;Integrated Security=SSPI";
         string qry = @"select * from employee";
         string upd = @"insert into employee(firstname,lastname)values(@firstname,@lastname)";

         SqlConnection conn = new SqlConnection(connString);

         try{
            SqlDataAdapter da = new SqlDataAdapter();
            da.SelectCommand = new SqlCommand(qry, conn);

            DataSet ds = new DataSet();   
            da.Fill(ds, "employee");

            DataTable dt = ds.Tables["employee"];

            DataRow newRow = dt.NewRow();
            newRow["firstname"] = "R";
            newRow["lastname"] = "B";
            dt.Rows.Add(newRow);

            foreach (DataRow row in dt.Rows){
               Console.WriteLine(
                  "{0} {1}",
                  row["firstname"].ToString().PadRight(15),
                  row["lastname"].ToString().PadLeft(25));
            }

            // Update employees
            SqlCommand cmd = new SqlCommand(upd, conn);
            cmd.Parameters.Add("@firstname", SqlDbType.NVarChar, 10, "firstname");
            cmd.Parameters.Add("@lastname",  SqlDbType.NVarChar, 20, "lastname");
            da.InsertCommand = cmd;
            da.Update(ds, "employee");
         } catch(Exception e) {
            Console.WriteLine("Error: " + e);
         } finally {
            conn.Close();
         }
      }  
   }