• DataTable添加行和列


    tablenullobjectdatasetc#c

    手动插入一行数据

            DataSet ds = tTalent.GetAllInfo();
            DataRow dr = ds.Tables[0].NewRow();
            dr["id"] = 0;
            dr["aboutType"] = "常见问题";
            dr["contents"] = "";
            ds.Tables[0].Rows.Add(dr);
            this.dlTalent.DataSource = ds.Tables[0].DefaultView;
            this.dlTalent.DataBind();

    插入一列数据

            DataTable dt = DBHelper.GetDataTable(sql);
            dt.Columns.Add("num", Type.GetType("System.Int32"));
            for (int i = 0; i < dt.Rows.Count; i++)
            {
                dt.Rows[i]["num"] = i + 1;
            }

    网络转载,以留备用  ↓↓↓↓↓↓↓↓↓

    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/sczw-maqing/p/3480258.html
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