Csharp/C Sharp/Database ADO.net/Update

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Creating Data Tables and Populating Them

/*
 * 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 CreatingDataTablesandPopulatingThem
    {
        static void Main(string[] args)
        {
            SqlConnection MyConnection = new SqlConnection(@"Data Source=(local); Initial Catalog = CaseManager; Integrated Security=true");
            SqlDataAdapter MyAdapter = new SqlDataAdapter("SELECT * FROM CaseInfo", MyConnection);
            DataSet MyDataSet = new DataSet();
            //Create a new DataTable
            DataTable MyTable2 = MyDataSet.Tables.Add("My2ndTable");
            //Adding Columns and Rows
            DataColumn myColumn = new DataColumn();
            myColumn.DataType = System.Type.GetType("System.Decimal");
            myColumn.AllowDBNull = false;
            myColumn.Caption = "Price";
            myColumn.ColumnName = "Price";
            myColumn.DefaultValue = 25;
            // Add the column to the table. 
            MyTable2.Columns.Add(myColumn);
            // Add 10 rows and set values. 
            DataRow myRow;
            for (int i = 0; i < 10; i++)
            {
                myRow = MyTable2.NewRow();
                myRow[0] = i + 1;
                // Be sure to add the new row to the DataRowCollection. 
                MyTable2.Rows.Add(myRow);
            }
            SqlCommandBuilder Builder = new SqlCommandBuilder(MyAdapter);
            MyAdapter.Update(MyDataSet, "My2ndTable");
        }
    }
}


Illustrates how to perform INSERT, UPDATE, and DELETE statements using ADO.NET

/*
Mastering Visual C# .NET
by Jason Price, Mike Gunderloy
Publisher: Sybex;
ISBN: 0782129110
*/
/*
  Example23_2.cs illustrates how to perform INSERT, UPDATE,
  and DELETE statements using ADO.NET
*/
using System;
using System.Data;
using System.Data.SqlClient;
public class Example23_2
{
  public static void DisplayDataTable(
    SqlDataAdapter mySqlDataAdapter,
    DataSet myDataSet,
    DataTable myDataTable
  )
  {
    // use the Clear() method of the DataSet object
    // to remove all the rows in the DataSet
    myDataSet.Clear();
    // use the Fill() method of the SqlDataAdapter object
    // to synchronize any changes made to the database
    // with the DataSet object
    mySqlDataAdapter.Fill(myDataSet, "Customers");
    // display the columns for each row in the DataTable,
    // using a DataRow object to access each row in the DataTable
    foreach (DataRow myDataRow in myDataTable.Rows)
    {
      Console.WriteLine("CustomerID = " + myDataRow["CustomerID"]);
      Console.WriteLine("CompanyName = " + myDataRow["CompanyName"]);
      Console.WriteLine("ContactName = " + myDataRow["ContactName"]);
      Console.WriteLine("Address = " + myDataRow["Address"]);
    }
  }
  public static void AddRow(
    SqlConnection mySqlConnection,
    SqlDataAdapter mySqlDataAdapter,
    DataSet myDataSet
  )
  {
    Console.WriteLine("\nAdding a new row with CustomerID of "T1COM"");
    // step 1: formulate a string containing the SQL statement
    string insertString =
      "INSERT INTO Customers (" +
      "  CustomerID, CompanyName, ContactName, Address" +
      ") VALUES (" +
      "  @CustomerID, @CompanyName, @ContactName, @Address" +
      ")";
    // step 2: create a SqlCommand object to hold the SQL statement
    SqlCommand mySqlCommand = mySqlConnection.CreateCommand();
    // step 3: set the CommandText property of the SqlCommand object to
    // the SQL string
    mySqlCommand.rumandText = insertString;
    // step 4: use the Add() method through the Parameters property
    // of the SqlCommand object to add the parameters to the SqlCommand
    // object
    mySqlCommand.Parameters.Add("@CustomerID", SqlDbType.NChar, 5);
    mySqlCommand.Parameters.Add("@CompanyName", SqlDbType.NVarChar, 40);
    mySqlCommand.Parameters.Add("@ContactName", SqlDbType.NVarChar, 30);
    mySqlCommand.Parameters.Add("@Address", SqlDbType.NVarChar, 60);
    // step 5: set the parameters to specified values using the
    // Value property
    mySqlCommand.Parameters["@CustomerID"].Value = "T1COM";
    mySqlCommand.Parameters["@CompanyName"].Value = "T1 Company";
    mySqlCommand.Parameters["@ContactName"].Value = "Jason Price";
    mySqlCommand.Parameters["@Address"].Value = "1 Main Street";
    // step 6: use the ExecuteNonQuery() method to run the
    // SQL statement
    mySqlCommand.ExecuteNonQuery();
  }
  public static void ModifyRow(
    SqlConnection mySqlConnection,
    SqlDataAdapter mySqlDataAdapter,
    DataSet myDataSet
  )
  {
    Console.WriteLine("\nModifying the new row");
    // step 1: formulate the SQL statement
    string updateString =
      "UPDATE Customers " +
      "SET " +
      "  CompanyName = @CompanyName, " +
      "  ContactName = @ContactName, " +
      "  Address = @Address " +
      "WHERE CustomerID = @CustomerID";
    // step 2: create a SqlCommand object to hold the SQL statement
    SqlCommand mySqlCommand = mySqlConnection.CreateCommand();
    // step 3: set the CommandText property of the SqlCommand object to
    // the SQL string
    mySqlCommand.rumandText = updateString;
    // step 4: use the Add() method through the Parameters property
    // to add the parameters
    mySqlCommand.Parameters.Add("@CustomerID", SqlDbType.NChar, 5);
    mySqlCommand.Parameters.Add("@CompanyName", SqlDbType.NVarChar, 40);
    mySqlCommand.Parameters.Add("@ContactName", SqlDbType.NVarChar, 30);
    mySqlCommand.Parameters.Add("@Address", SqlDbType.NVarChar, 60);
    // step 5: set the parameters to values using the Value property
    mySqlCommand.Parameters["@CustomerID"].Value = "T1COM";
    mySqlCommand.Parameters["@CompanyName"].Value = "Widgets Inc.";
    mySqlCommand.Parameters["@ContactName"].Value = "John Smith";
    mySqlCommand.Parameters["@Address"].Value = "1 Any Street";
    // step 6: use the ExecuteNonQuery() method to run the
    // SQL statement
    mySqlCommand.ExecuteNonQuery();
  }
  public static void RemoveRow(
    SqlConnection mySqlConnection,
    SqlDataAdapter mySqlDataAdapter,
    DataSet myDataSet
  )
  {
    Console.WriteLine("\nRemoving the new row");
    // step 1: formulate the SQL statement
    string deleteString =
      "DELETE FROM Customers " +
      "WHERE CustomerID = @CustomerID";
    // step 2: create a SqlCommand object to hold the SQL statement
    SqlCommand mySqlCommand = mySqlConnection.CreateCommand();
    // step 3: set the CommandText property of the SqlCommand object to
    // the SQL string
    mySqlCommand.rumandText = deleteString;
    // step 4: use the Add() method through the Parameters property
    // to add the parameter
    mySqlCommand.Parameters.Add("@CustomerID", SqlDbType.NChar, 5);
    // step 5: set the parameters to values using the Value property
    mySqlCommand.Parameters["@CustomerID"].Value = "T1COM";
    // step 6: use the ExecuteNonQuery() method to run the
    // SQL statement
    mySqlCommand.ExecuteNonQuery();
  }
  public static void Main()
  {
    // formulate a string containing the details of the
    // database connection
    string connectionString =
      "server=localhost;database=Northwind;uid=sa;pwd=sa";
    // create a SqlConnection object to connect to the
    // database, passing the connection string to the constructor
    SqlConnection mySqlConnection =
      new SqlConnection(connectionString);
    // formulate a SELECT statement to retrieve the
    // CustomerID, CompanyName, ContactName, and Address
    // columns for rows from the Customers table
    string selectString =
      "SELECT CustomerID, CompanyName, ContactName, Address " +
      "FROM Customers " +
      "WHERE CustomerID IN ("ALFKI", "T1COM")";
    // create a SqlCommand object to hold the SELECT statement
    SqlCommand mySqlCommand = mySqlConnection.CreateCommand();
    // set the CommandText property of the SqlCommand object to
    // the SELECT string
    mySqlCommand.rumandText = selectString;
    // create a SqlDataAdapter object
    SqlDataAdapter mySqlDataAdapter = new SqlDataAdapter();
    // set the SelectCommand property of the SqlAdapter object
    // to the SqlCommand object
    mySqlDataAdapter.SelectCommand = mySqlCommand;
    // create a DataSet object to store the results of
    // the SELECT statement
    DataSet myDataSet = new DataSet();
    // open the database connection using the
    // Open() method of the SqlConnection object
    mySqlConnection.Open();
    // use the Fill() method of the SqlDataAdapter object to
    // retrieve the rows from the table, storing the rows locally
    // in a DataTable of the DataSet object
    string dataTableName = "Customers";
    Console.WriteLine("Retrieving a row from the Customers table");
    mySqlDataAdapter.Fill(myDataSet, dataTableName);
    // get the DataTable object from the DataSet object
    DataTable myDataTable = myDataSet.Tables[dataTableName];
    // display the rows in the DataTable object
    DisplayDataTable(mySqlDataAdapter, myDataSet, myDataTable);
    // add a new row
    AddRow(mySqlConnection, mySqlDataAdapter, myDataSet);
    DisplayDataTable(mySqlDataAdapter, myDataSet, myDataTable);
    // modify the new row
    ModifyRow(mySqlConnection, mySqlDataAdapter, myDataSet);
    DisplayDataTable(mySqlDataAdapter, myDataSet, myDataTable);
    // remove the new row
    RemoveRow(mySqlConnection, mySqlDataAdapter, myDataSet);
    DisplayDataTable(mySqlDataAdapter, myDataSet, myDataTable);
    // close the database connection using the Close() method
    // of the SqlConnection object
    mySqlConnection.Close();
  }
}


Update A DataSource

/*
 * 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.OleDb;
namespace Client.Chapter_13___ADO.NET
{
    public class UpdatingADataSource
    {
        static void Main(string[] args)
        {
            OleDbConnection MyConnection = new OleDbConnection(@"Provider=Microsft.Jet.OLEDB.4.0; Data Source = c:\MyAccessDB.mdb");
            OleDbDataAdapter MyAdapter = new OleDbDataAdapter("SELECT Column1, Column2, Column3 FROM MyTable", MyConnection);
            DataSet MyDataSet = new DataSet();
            MyAdapter.Fill(MyDataSet, "MyTable");
            MyDataSet.Tables[0].Rows[3]["Column3"] = "Test";
            OleDbCommandBuilder MyBuilder = new OleDbCommandBuilder(MyAdapter);
            MyAdapter.Update(MyDataSet.Tables[0]);
        }
    }
}


Update Data Using Commond Builder

/*
 * 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 UpdatingDataUsingCommondBuilder
    {
        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);
            DataSet MyDataSet = new DataSet();
            MyDataAdapter.Fill(MyDataSet);
            MyDataSet.Tables[0].Rows[0][0] = 55;
            SqlCommandBuilder MyCmd = new SqlCommandBuilder(MyDataAdapter);
            MyDataAdapter.Update(MyDataSet);
        }
    }
}


Update Data Using Sql Statements 2

/*
 * 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 UpdatingDataUsingSqlStatements
    {
        static void Main(string[] args)
        {
            SqlConnection MyConnection = new SqlConnection(@"Data Source=(local); Initial Catalog = CaseManager; Integrated Security=true");
            MyConnection.Open();
            String MyString = "UPDATE Test SET Contact = "Lee"";
            SqlCommand MyCmd = new SqlCommand(MyString, MyConnection);
            MyCmd.ExecuteScalar();
            MyConnection.Close();
        }
    }
}


Update table using SqlDataAdapter

using System;
using System.Data;
using System.Data.SqlClient;
   class PropagateChanges {
      static void Main(){
         string connString = "server=(local)\\SQLEXPRESS;database=MyDatabase;Integrated Security=SSPI";
         string qry = @"select * from employee ";
         string upd = @"update employee set firstname = @firstname where id = @id";
         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"];
            dt.Rows[0]["firstname"] = "W";
            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,15, "firstname");
            SqlParameter parm = cmd.Parameters.Add("@id",SqlDbType.Int,4,"id");
            parm.SourceVersion = DataRowVersion.Original;
            da.UpdateCommand = cmd;
            da.Update(ds, "employee");
         } catch(Exception e) {
            Console.WriteLine("Error: " + e);
         } finally {
            conn.Close();
         }
      }  
   }


Use DataTable to update table in Database

using System;
using System.Data;
using System.Data.SqlClient;
   class PropagateAddsBuilder {
      static void Main() {
         string connString = "server=(local)\\SQLEXPRESS;database=MyDatabase;Integrated Security=SSPI";
         string qry = @"select * from employee";
 
         SqlConnection conn = new SqlConnection(connString);
         try {
            SqlDataAdapter da = new SqlDataAdapter();
            da.SelectCommand = new SqlCommand(qry, conn);
            SqlCommandBuilder cb = new SqlCommandBuilder(da);
            DataSet ds = new DataSet();   
            da.Fill(ds, "employee");
            DataTable dt = ds.Tables["employee"];
            // Add a row
            DataRow newRow = dt.NewRow();
            newRow["firstname"] = "y";
            newRow["lastname"] = "y";
            dt.Rows.Add(newRow);
            foreach (DataRow row in dt.Rows){
               Console.WriteLine(
                  "{0} {1}",
                  row["firstname"].ToString().PadRight(15),
                  row["lastname"].ToString().PadLeft(25));
            }
            da.Update(ds, "employee");
         } catch(Exception e)  {
            Console.WriteLine("Error: " + e);
         } finally {
            conn.Close();
         }
      }  
   }


Using Data Table Mappings

/*
 * 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.rumon;
using System.Data.SqlClient;
namespace Client.Chapter_13___ADO.NET
{
    public class UsingDataTableMappings
    {
        static void Main(string[] args)
        {
            SqlConnection SConn = new SqlConnection("Data Source=(local); Initial Catalog = CaseManager; Integrated Security=true");
            SqlDataAdapter da = new SqlDataAdapter("SELECT ID, Contact, Email FROM CaseInfo", SConn);
            DataSet ds = new DataSet();
            DataTableMapping custMap = da.TableMappings.Add("CaseInfo", "MyDatabase");
            custMap.ColumnMappings.Add("ID", "CaseNumber");
            custMap.ColumnMappings.Add("Contact", "MyContact");
            custMap.ColumnMappings.Add("Email", "Email Address");
            da.Fill(ds);
        }
    }
}
Источник — «http://nfex.ru/index.php?title=Csharp/C_Sharp/Database_ADO.net/Update&oldid=1042»