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  • 动态创建DataTable[转]

    CoreDS.Tables["sys"].PrimaryKey = new DataColumn[] { CoreDS.Tables["sys"].Columns["id"] };

    DataTable添加列和行的方法

    C#  
    方法一:

    DataTable  tblDatas = newDataTable("Datas");
    DataColumn dc = null;

    //赋值给dc,是便于对每一个datacolumn的操作
    dc =tblDatas.Columns.Add("ID",Type.GetType("System.Int32"));
    dc.AutoIncrement= true;//自动增加
    dc.AutoIncrementSeed = 1;//起始为1
    dc.AutoIncrementStep = 1;//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 = newDataTable("Datas");
    tblDatas.Columns.Add("ID", Type.GetType("System.Int32"));
    tblDatas.Columns[0].AutoIncrement = true;
    tblDatas.Columns[0].AutoIncrementSeed = 1;
    tblDatas.Columns[0].AutoIncrementStep = 1;

    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(newobject[]{null,"a","b","c"});
    tblDatas.Rows.Add(newobject[] { 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 =50;

    // 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_r_r = "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_r_r = "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
     DataViewview = new DataView(table);
    dg.DataSource = view;

    dg.DataBind();

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  • 原文地址:https://www.cnblogs.com/wangchuang/p/3093092.html
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