// 构造datatableDataTable dt = new DataTable("test_table");dt.Columns.AddRange(new DataColumn[]{ new DataColumn("name", typeof(string)), new DataColumn("sex", typeof(string)), new DataColumn("score", typeof(int))});dt.Rows.Add(new Object[] {"张三", "男", 1});dt.Rows.Add(new Object[] {"张三", "男", 4});dt.Rows.Add(new Object[] {"李四", "男", 100});dt.Rows.Add(new Object[] {"张三", "女", 90});dt.Rows.Add(new Object[] {"王五", "女", 77});Console.WriteLine(dt.Rows[0]["name"]);Console.WriteLine(dt.Rows[0]["sex"]);dt.Rows[0]["score"] = 80;Console.WriteLine(dt.Rows[0]["score"]);Console.WriteLine(dt.TableName);Console.WriteLine("test_table has " + dt.Rows.Count + " rows");// 行内查找DataRow[] rows = dt.Select("name=" + "‘张三‘" + "and sex=" + "‘男‘");DataTable temp = dt.Clone();foreach (DataRow row in rows){ Console.WriteLine(row["name"]); temp.Rows.Add(row.ItemArray);}// 统计Console.WriteLine(temp.Compute("sum(score)", ""));Console.WriteLine();// datatable的copy和cloneDataTable dt2 = dt.Copy();Console.WriteLine(dt2.Rows.Count);Console.WriteLine(dt2.Rows[0]["score"]);DataTable dt3 = dt.Clone();dt3.Rows.Add(new object[] {"abc", "女", 80});dt3.Rows.Add(new object[] {"drt", "男", 90});// 构造新行DataRow dr = dt3.NewRow();dr[0] = "jkj";dr[1] = "女";dr[2] = 100;dt3.Rows.Add(dr);Console.WriteLine(dt3.Rows.Count);// 写入csv文件if (File.Exists(dt.TableName + ".csv")){ File.Delete(dt.TableName + ".csv");}FileStream fs = new FileStream(dt.TableName + ".csv", FileMode.Create, FileAccess.Write);StreamWriter sw = new StreamWriter(fs, Encoding.Default);var data = string.Empty;for (var i = 0; i < dt.Columns.Count; i++){ data += dt.Columns[i].ColumnName; if (i < dt.Columns.Count - 1) { data += ","; }}sw.WriteLine(data);for (var i = 0; i < dt.Rows.Count; i++){ data = string.Empty; for (var j = 0; j < dt.Columns.Count; j++) { data += dt.Rows[i][j].ToString(); if (j < dt.Columns.Count - 1) { data += ","; } } sw.WriteLine(data);}sw.Close();fs.Close();Console.ReadKey();