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#region DataTable筛选，排序返回符合条件行组成的新DataTable或直接用DefaultView按条件返回 /// <summary> /// DataTable筛选，排序返回符合条件行组成的新DataTable或直接用DefaultView按条件返回 /// eg:SortExprDataTable(dt,"Sex=‘男‘","Time Desc",1) /// </summary> /// <param name="dt">传入的DataTable</param> /// <param name="strExpr">筛选条件</param> /// <param name="strSort">排序条件</param> /// <param name="mode">1,直接用DefaultView按条件返回,效率较高;2,DataTable筛选，排序返回符合条件行组成的新DataTable</param> public
static DataTable SortDataTable(DataTable dt, string
strExpr, string
strSort, int
mode) { switch
(mode) { case
1: //方法一 直接用DefaultView按条件返回 dt.DefaultView.RowFilter = strExpr; dt.DefaultView.Sort = strSort; return
dt; case
2: //方法二 DataTable筛选，排序返回符合条件行组成的新DataTable DataTable dt1 = new
DataTable(); DataRow[] GetRows = dt.Select(strExpr, strSort); //复制DataTable dt结构不包含数据 dt1 = dt.Clone(); foreach
(DataRow row in
GetRows) { dt1.Rows.Add(row.ItemArray); } return
dt1; default: return
dt; } } #endregion harp] view plaincopyprint?#region 获取DataTable前几条数据 /// <summary> /// 获取DataTable前几条数据 /// </summary> /// <param name="TopItem">前N条数据</param> /// <param name="oDT">源DataTable</param> /// <returns></returns> public
static DataTable DtSelectTop(int
TopItem, DataTable oDT) { if
(oDT.Rows.Count < TopItem) return
oDT; DataTable NewTable = oDT.Clone(); DataRow[] rows = oDT.Select("1=1"); for
(int
i = 0; i < TopItem; i++) { NewTable.ImportRow((DataRow)rows[i]); } return
NewTable; } #endregion #region 获取DataTable中指定列的数据 /// <summary> /// 获取DataTable中指定列的数据 /// </summary> /// <param name="dt">数据源</param> /// <param name="tableName">新的DataTable的名词</param> /// <param name="strColumns">指定的列名集合</param> /// <returns>返回新的DataTable</returns> public
static DataTable GetTableColumn(DataTable dt, string
tableName, params
string[] strColumns) { DataTable dtn = new
DataTable(); if
(dt == null) { throw
new ArgumentNullException("参数dt不能为null"); } try { dtn = dt.DefaultView.ToTable(tableName, true, strColumns); } catch
(Exception e) { throw
new Exception(e.Message); } return
dtn; } #endregion |
对datatable操作，查询,布布扣,bubuko.com
原文：http://www.cnblogs.com/lhws/p/3652726.html