Datatble新增(2)

 

 column.ReadOnly = true;

        column.Unique =true;

 

        // Add the column to the DataColumnCollection.

        table.Columns.Add(column);

 

        // Create second column.

        column = new DataColumn();

        column.DataType = System.Type.GetType("System.String");

        column.ColumnName ="ChildItem";

        column.AutoIncrement =false;

        column.Caption ="ChildItem";

        column.ReadOnly =false;

        column.Unique =false;

        table.Columns.Add(column);

 

        // Create third column.

        column = new DataColumn();

        column.DataType = System.Type.GetType("System.Int32");

        column.ColumnName ="ParentID";

        column.AutoIncrement =false;

        column.Caption ="ParentID";

        column.ReadOnly =false;

        column.Unique =false;

        table.Columns.Add(column);

 

        dataSet.Tables.Add(table);

 

        // Create three sets of DataRow objects,

        // five rows each, and add to DataTable.

        for (int i = 0; i <= 4; i++)

        {

            row = table.NewRow();

            row["childID"] = i;

            row["ChildItem"] ="Item " + i;

            row["ParentID"] = 0;

            table.Rows.Add(row);

        }

        for (int i = 0; i <= 4; i++)

        {

            row = table.NewRow();

            row["childID"] = i + 5;

            row["ChildItem"] ="Item " + i;

            row["ParentID"] = 1;

            table.Rows.Add(row);

        }

        for (int i = 0; i <= 4; i++)

        {

            row = table.NewRow();

            row["childID"] = i + 10;

            row["ChildItem"] ="Item " + i;

            row["ParentID"] = 2;

            table.Rows.Add(row);

        }

    }

 

    privatevoid MakeDataRelation()

    {

        // DataRelation requires two DataColumn

        // (parent and child) and a name.

        DataColumn parentColumn =

            dataSet.Tables["ParentTable"].Columns["id"];

        DataColumn childColumn =

            dataSet.Tables["ChildTable"].Columns["ParentID"];

        DataRelation relation =new

            DataRelation("parent2Child", parentColumn, childColumn);

        dataSet.Tables["ChildTable"].ParentRelations.Add(relation);

    }