(转)C#创建datatable

 Asp.net DataTable添加列和行的方法
 方法一:

 DataTable tblDatas = new DataTable("Datas");
 DataColumn dc = null;
 dc = tblDatas.Columns.Add("ID", Type.GetType("System.Int32"));
 dc.AutoIncrement = true;//自动增加
 dc.AutoIncrementSeed = ;//起始为1
 dc.AutoIncrementStep = ;//步长为1
 dc.AllowDBNull = false;//

 dc = tblDatas.Columns.Add("Product", Type.GetType("System.String"));
 dc = tblDatas.Columns.Add("Version", Type.GetType("System.String"));
 dc = tblDatas.Columns.Add("Description", Type.GetType("System.String"));

 DataRow newRow;
 newRow = tblDatas.NewRow();
 newRow["Product"] = "大话西游";
 newRow["Version"] = "2.0";
 newRow["Description"] = "我很喜欢";
 tblDatas.Rows.Add(newRow);

 newRow = tblDatas.NewRow();
 newRow["Product"] = "梦幻西游";
 newRow["Version"] = "3.0";
 newRow["Description"] = "比大话更幼稚";
 tblDatas.Rows.Add(newRow);

 方法二:

 DataTable tblDatas = new DataTable("Datas");
 tblDatas.Columns.Add("ID", Type.GetType("System.Int32"));
 tblDatas.Columns[].AutoIncrement = true;
 tblDatas.Columns[].AutoIncrementSeed = ;
 tblDatas.Columns[].AutoIncrementStep = ;

 tblDatas.Columns.Add("Product", Type.GetType("System.String"));
 tblDatas.Columns.Add("Version", Type.GetType("System.String"));
 tblDatas.Columns.Add("Description", Type.GetType("System.String"));

 tblDatas.Rows.Add(new object[]{null,"a","b","c"});
 tblDatas.Rows.Add(new object[] { null, "a", "b", "c" });
 tblDatas.Rows.Add(new object[] { null, "a", "b", "c" });
 tblDatas.Rows.Add(new object[] { null, "a", "b", "c" });
 tblDatas.Rows.Add(new object[] { null, "a", "b", "c" });

 方法三：
 DataTable table = new DataTable ();

 //创建table的第一列
 DataColumn priceColumn = new DataColumn();
 //该列的数据类型
 priceColumn.DataType = System.Type.GetType("System.Decimal");
 //该列得名称
 priceColumn.ColumnName = "price";
 //该列得默认值
 priceColumn.DefaultValue = ;

 // 创建table的第二列
 DataColumn taxColumn = new DataColumn();
 taxColumn.DataType = System.Type.GetType("System.Decimal");
 //列名
 taxColumn.ColumnName = "tax";
 //设置该列得表达式，用于计算列中的值或创建聚合列
 taxColumn.Expression = "price * 0.0862";
 // Create third column.
 DataColumn totalColumn = new DataColumn();
 totalColumn.DataType = System.Type.GetType("System.Decimal");
 totalColumn.ColumnName = "total";
 //该列的表达式，值是得到的是第一列和第二列值得和
 totalColumn.Expression = "price + tax";

 // 将所有的列添加到table上
 table.Columns.Add(priceColumn);
 table.Columns.Add(taxColumn);
 table.Columns.Add(totalColumn);

 //创建一行
 DataRow row = table.NewRow();
 //将此行添加到table中
 table.Rows.Add(row);

 //将table放在试图中
 DataView view = new DataView(table);
 dg.DataSource = view;

 dg.DataBind();