Csharp/C Sharp by API/System.Data/DataTable — различия между версиями

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м (1 версия)
 
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Текущая версия на 12:12, 26 мая 2010

DataTable.Columns

  
using System;
using System.Data;
using System.Data.SqlClient;
class PopDataset
{
   static void Main()
   {
      string connString = "server=(local)\\SQLEXPRESS;database=MyDatabase;Integrated Security=SSPI";
      string sql = @"select * from employee";
      SqlConnection conn = new SqlConnection(connString);
      try
      {
         conn.Open();
         SqlDataAdapter da = new SqlDataAdapter(sql, conn);
         DataSet ds = new DataSet();    
         da.Fill(ds, "employee");
         DataTable dt = ds.Tables["employee"];
         foreach (DataRow row in dt.Rows)
         {
            foreach (DataColumn col in dt.Columns)
               Console.WriteLine(row[col]);
            Console.WriteLine("".PadLeft(20, "="));
         }
      }
      catch(Exception e)
      {
         Console.WriteLine("Error: " + e);
      }
      finally
      {
         conn.Close();
      }
   }  
}


DataTable.Columns.Add

  


using System;
using System.Data;
using System.Data.SqlClient;
    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");
        }
    }


DataTable.MinimumCapacity

 
using System;
using System.Drawing;
using System.Collections;
using System.Data;
using System.ruponentModel;
using System.Windows.Forms;
public class GridBind : System.Windows.Forms.Form
{
    private System.Windows.Forms.DataGrid dataGrid1 = new System.Windows.Forms.DataGrid ();
    private DataSet dataset = new DataSet("ContactData");
    public GridBind()
    {
        dataGrid1.BeginInit ();
        dataGrid1.Location = new System.Drawing.Point (8, 16);
        dataGrid1.Size = new System.Drawing.Size (472, 224);
        dataGrid1.DataMember = "";
        this.AutoScaleBaseSize = new System.Drawing.Size (5, 13);
        this.FormBorderStyle = System.Windows.Forms.FormBorderStyle.Fixed3D;
        this.ClientSize = new System.Drawing.Size (486, 251);
        this.Controls.Add (this.dataGrid1);
        dataGrid1.EndInit ();
        DataTable t=new DataTable("Contacts");
        t.Columns.Add("First",typeof(System.String));
        t.Columns.Add("Name",typeof(System.String));
        t.Columns.Add("Company",typeof(System.String));
        t.Columns.Add("Title",typeof(System.String));
        t.Columns.Add("Phone",typeof(System.String));
        t.MinimumCapacity=100;
        dataset.Tables.Add(t);
        this.dataGrid1.SetDataBinding(dataset.Tables["Contacts"],"");
    }
    static void Main()
    {
        Application.Run(new GridBind());
    }
}


DataTable.NewRow()

  


using System;
using System.Data;
using System.Data.SqlClient;
    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");
        }
    }


DataTable.Rows

  
using System;
using System.IO;
using System.Data;
public class MainClass {
    static void Main(string[] args) {
        if (args.Length != 1)
            return;
        FileStream fs = new FileStream(args[0], FileMode.Open);
        DataSet ds = new DataSet();
        ds.ReadXml(fs);
        // Use a DataTable to display the members.
        DataTable mt = ds.Tables["member"];
        for (int row = 0; row < mt.Rows.Count; row++) {
            for (int col = 0; col < mt.Columns.Count - 1; col++) {
                Console.WriteLine("{0,-10}{1}",
                    mt.Columns[col].Caption,
                    mt.Rows[row][col].ToString().Trim());
            }
            Console.WriteLine();
        }
        fs.Close();
    }
}


DataTable.Rows.Add

  


using System;
using System.Data;
using System.Data.SqlClient;
    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");
        }
    }