本文實例講述了C#中DataTable實作行列轉換的方法。分享給大家供大家參考。具體實現方法如下:
protected void Page_Load(object sender, EventArgs e) { if (!IsPostBack) { DataTable tt = GetCrossTable(CreateDT()); GridView1.DataSource = tt; GridView1.DataBind(); } } //创建DataTable protected DataTable CreateDT() { DataTable tblDatas = new DataTable("Datas"); //数据列 tblDatas.Columns.Add("姓名", Type.GetType("System.String")); tblDatas.Columns.Add("科目", Type.GetType("System.String")); tblDatas.Columns.Add("分数", Type.GetType("System.Int32")); tblDatas.Rows.Add(new object[] { "张三", "语文", 89 }); tblDatas.Rows.Add(new object[] { "张三", "数学", 90 }); tblDatas.Rows.Add(new object[] { "张三", "英语", 79 }); tblDatas.Rows.Add(new object[] { "张三", "地理", 70 }); tblDatas.Rows.Add(new object[] { "张三", "生物", 95 }); tblDatas.Rows.Add(new object[] { "李四", "语文", 87 }); tblDatas.Rows.Add(new object[] { "李四", "英语", 86 }); tblDatas.Rows.Add(new object[] { "李四", "地理", 82 }); tblDatas.Rows.Add(new object[] { "王五", "语文", 81 }); tblDatas.Rows.Add(new object[] { "王五", "数学", 70 }); tblDatas.Rows.Add(new object[] { "王五", "英语", 88 }); tblDatas.Rows.Add(new object[] { "王五", "生物", 96 }); return tblDatas; } /// <summary> /// 将DataTable的第二列的值转化为列 //(即将原来的行表,转化成交叉表,没有对应值则默认"0") /// </summary> /// <param name="dt">必须三列,第三列为值</param> /// <returns></returns> public static DataTable GetCrossTable(DataTable dt) { if (dt == null || dt.Columns.Count != 3 || dt.Rows.Count == 0) { return dt; } else { DataTable result = new DataTable(); result.Columns.Add(dt.Columns[0].ColumnName); DataTable dtColumns = dt.DefaultView.ToTable("dtColumns", true, dt.Columns[1].ColumnName); for (int i = 0; i < dtColumns.Rows.Count; i++) { string colName; if (dtColumns.Rows[1][0] is DateTime) { colName = Convert.ToDateTime(dtColumns.Rows[i][0]).ToString(); } else { colName = dtColumns.Rows[i][0].ToString(); } result.Columns.Add(colName); result.Columns[i + 1].DefaultValue = "0"; } DataRow drNew = result.NewRow(); drNew[0] = dt.Rows[0][0]; string rowName = drNew[0].ToString(); foreach (DataRow dr in dt.Rows) { string colName = dr[1].ToString(); double dValue = Convert.ToDouble(dr[2]); if (dr[0].ToString().Equals(rowName, StringComparison.CurrentCultureIgnoreCase)) { drNew[colName] = dValue.ToString(); } else { result.Rows.Add(drNew); drNew = result.NewRow(); drNew[0] = dr[0]; rowName = drNew[0].ToString(); drNew[colName] = dValue.ToString(); } } result.Rows.Add(drNew); return result; } }
希望本文所述對大家的C#程式設計有所幫助。
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