System.Data.Tests.DataColumnCollectionTest2.Add C# (CSharp) Метод

        public void Add()
        {
            DataColumn dc = null;
            DataTable dt = new DataTable();

            //----------------------------- check default --------------------
            dc = dt.Columns.Add();
            // Add column 1
            Assert.Equal("Column1", dc.ColumnName);

            // Add column 2
            dc = dt.Columns.Add();
            Assert.Equal("Column2", dc.ColumnName);

            dc = dt.Columns.Add();
            // Add column 3
            Assert.Equal("Column3", dc.ColumnName);

            dc = dt.Columns.Add();
            // Add column 4
            Assert.Equal("Column4", dc.ColumnName);

            dc = dt.Columns.Add();
            // Add column 5
            Assert.Equal("Column5", dc.ColumnName);
            Assert.Equal(5, dt.Columns.Count);

            //----------------------------- check Add/Remove from begining --------------------
            dt = initTable();

            dt.Columns.Remove(dt.Columns[0]);
            dt.Columns.Remove(dt.Columns[0]);
            dt.Columns.Remove(dt.Columns[0]);

            // check column 4 - remove - from begining
            Assert.Equal("Column4", dt.Columns[0].ColumnName);

            // check column 5 - remove - from begining
            Assert.Equal("Column5", dt.Columns[1].ColumnName);
            Assert.Equal(2, dt.Columns.Count);

            dt.Columns.Add();
            dt.Columns.Add();
            dt.Columns.Add();
            dt.Columns.Add();

            // check column 0 - Add new  - from begining
            Assert.Equal("Column4", dt.Columns[0].ColumnName);

            // check column 1 - Add new - from begining
            Assert.Equal("Column5", dt.Columns[1].ColumnName);

            // check column 2 - Add new - from begining
            Assert.Equal("Column6", dt.Columns[2].ColumnName);

            // check column 3 - Add new - from begining
            Assert.Equal("Column7", dt.Columns[3].ColumnName);

            // check column 4 - Add new - from begining
            Assert.Equal("Column8", dt.Columns[4].ColumnName);

            // check column 5 - Add new - from begining
            Assert.Equal("Column9", dt.Columns[5].ColumnName);

            //----------------------------- check Add/Remove from middle --------------------

            dt = initTable();

            dt.Columns.Remove(dt.Columns[2]);
            dt.Columns.Remove(dt.Columns[2]);
            dt.Columns.Remove(dt.Columns[2]);

            // check column 0 - remove - from Middle
            Assert.Equal("Column1", dt.Columns[0].ColumnName);

            // check column 1 - remove - from Middle
            Assert.Equal("Column2", dt.Columns[1].ColumnName);

            dt.Columns.Add();
            dt.Columns.Add();
            dt.Columns.Add();
            dt.Columns.Add();

            // check column 0 - Add new  - from Middle
            Assert.Equal("Column1", dt.Columns[0].ColumnName);

            // check column 1 - Add new - from Middle
            Assert.Equal("Column2", dt.Columns[1].ColumnName);

            // check column 2 - Add new - from Middle
            Assert.Equal("Column3", dt.Columns[2].ColumnName);

            // check column 3 - Add new - from Middle
            Assert.Equal("Column4", dt.Columns[3].ColumnName);

            // check column 4 - Add new - from Middle
            Assert.Equal("Column5", dt.Columns[4].ColumnName);

            // check column 5 - Add new - from Middle
            Assert.Equal("Column6", dt.Columns[5].ColumnName);

            //----------------------------- check Add/Remove from end --------------------

            dt = initTable();

            dt.Columns.Remove(dt.Columns[4]);
            dt.Columns.Remove(dt.Columns[3]);
            dt.Columns.Remove(dt.Columns[2]);

            // check column 0 - remove - from end
            Assert.Equal("Column1", dt.Columns[0].ColumnName);

            // check column 1 - remove - from end
            Assert.Equal("Column2", dt.Columns[1].ColumnName);

            dt.Columns.Add();
            dt.Columns.Add();
            dt.Columns.Add();
            dt.Columns.Add();

            // check column 0 - Add new  - from end
            Assert.Equal("Column1", dt.Columns[0].ColumnName);

            // check column 1 - Add new - from end
            Assert.Equal("Column2", dt.Columns[1].ColumnName);

            // check column 2 - Add new - from end
            Assert.Equal("Column3", dt.Columns[2].ColumnName);

            // check column 3 - Add new - from end
            Assert.Equal("Column4", dt.Columns[3].ColumnName);

            // check column 4 - Add new - from end
            Assert.Equal("Column5", dt.Columns[4].ColumnName);

            // check column 5 - Add new - from end
            Assert.Equal("Column6", dt.Columns[5].ColumnName);
        }