1、创建DataTable对象DataTable dt = new DataTable("Table_AX"); 2、为DataTable创建列//方式一(我觉得这种好)dt.Columns.Add("column0", System.Type.GetType("System.String"));//方式二DataColumn dc = new DataColumn("column0", typeof(string));
DataColumn dc = new DataColumn("column1", System.Type.GetType("System.Boolean"));
dt.Columns.Add(dc); 3、添加数据DataRow dr = dt.NewRow();
dr["column0"] = "AX";
dr["column1"] = true;
dt.Rows.Add(dr); 4、移除数据dt.Columns.Remove("column0"); 4、判断是否有数据//判断是否有数据if (dt.Rows.Count > 0)
{ //有} 5、查询DataRow[] drs = dt.Select("column1 is null");
DataRow[] drss = dt.Select("column0 = 'AX'");
//返回第一条DataRow dr = dt.Select("column1 is null").First();//多条件用and连接DataRow[] rows = dt.Select("column0 = 'AX' and column1 == true").First(); 6、复制
//复制一个DataTable(有数据)DataTable dtNew = dt.Copy();//复制一个空的DataTable(无数据)DataTable dtOnlyScheme = dt.Clone();//将 DataRow 复制到 DataTable 中,保留任何属性设置以及初始值和当前值DataRow[] rows = dt.Select("column0 = 'AX' and column1 == true").First();foreach (DataRow row in rows)
{
dtNew.ImportRow(row);//复制行数据}
7、DataRow赋值
DataRow drOperate = dt.Rows[0];//方式一drOperate["column0"] = "AXzhz";
drOperate["column1"] = false;//方式二drOperate[0] = "AXzhz";
drOperate[1] = false;//方式三dt.Rows[0]["column0"] = "AXzhz";
dt.Rows[0]["column1"] = false;//方式四dt.Rows[0][0] = "AXzhz";
dt.Rows[0][1] = false;
8、把DataRow数据存到DataTable中dtOnlyScheme.Rows.Add(dt.Rows[0].ItemArray); 9、转成字符串System.IO.StringWriter sw = new System.IO.StringWriter();
System.Xml.XmlTextWriter xw = new System.Xml.XmlTextWriter(sw);
dt.WriteXml(xw);//此处DataTable必须有名字string s = sw.ToString(); dt.DefaultView.RowFilter = "column1 <> true";dt.DefaultView.RowFilter = "column1 = true"; 第一种方法是直接从一个datatable转到另一个datatable private static DataTable GetNewTable(DataTable DT, string strCondition) { DataTable TempDT = DT.Clone(); DataRow[] Rows = DT.Select(strCondition); foreach (DataRow DR in Rows) { TempDT.ImportRow(DR); } return TempDT; } 第二种方法 public DataTable ToDataTable(DataRow[] rows) { if (rows == null || rows.Length == 0) return null; DataTable tmp = rows[0].Table.Clone(); // 复制DataRow的表结构 foreach (DataRow row in rows) tmp.Rows.Add(row.ItemArray); // 将DataRow添加到DataTable中 return tmp; } 回到顶部
11、排序dt.DefaultView.Sort = "column0 ,column1 ASC";
dt = dt.DefaultView.ToTable(); 12、判断一个字符串是否为DataTable的列名bool flag = dt.Columns.Contains("AX"); 13、取值
string str =dt.Rows[第几行]["字段名"].ToString();
string str =dt.Rows[第几行][第几列].ToString();//for循环for (int i = 0; i < dt.Rows.Count; i++)
{ string str = dt.Rows[i]["字段名"].ToString(); string str = dt.Rows[i][第几列].ToString();
}//foreach循环foreach (DataRow dr in dt.Rows)
{ string str = dr["字段名"].ToString();
}
//创建DataTable对象DataTable dt = new DataTable("Table_AX");//为DataTable创建列//方式一(我觉得这种好)dt.Columns.Add("column0", System.Type.GetType("System.String"));//方式二DataColumn dc = new DataColumn("column1", System.Type.GetType("System.Boolean"));
dt.Columns.Add(dc);//添加数据DataRow dr = dt.NewRow();
dr["column0"] = "AX";
dr["column1"] = true;
dt.Rows.Add(dr);
//判断是否有数据if (dt.Rows.Count > 0)
{ //有}//查询DataRow[] drs = dt.Select("column1 is null");
DataRow[] drss = dt.Select("column0 = 'AX'");
//复制一个DataTable(有数据)DataTable dtNew = dt.Copy();//复制一个空的DataTable(无数据)DataTable dtOnlyScheme = dt.Clone();//给DataRow赋值的三种方式DataRow drOperate = dt.Rows[0];//方式一drOperate["column0"] = "AXzhz";
drOperate["column1"] = false;//方式二drOperate[0] = "AXzhz";
drOperate[1] = false;//方式三dt.Rows[0]["column0"] = "AXzhz";
dt.Rows[0]["column1"] = false;//方式四dt.Rows[0][0] = "AXzhz";
dt.Rows[0][1] = false;//把DataRow数据存到DataTable中dtOnlyScheme.Rows.Add(dt.Rows[0].ItemArray);
//转成字符串System.IO.StringWriter sw = new System.IO.StringWriter();
System.Xml.XmlTextWriter xw = new System.Xml.XmlTextWriter(sw);
dt.WriteXml(xw);//此处DataTable必须有名字string s = sw.ToString();//筛选数据(详见DefaultView文章)dt.DefaultView.RowFilter = "column1 <> true";
dt.DefaultView.RowFilter = "column1 = true";//排序dt.DefaultView.Sort = "column0 ,column1 ASC";
dt = dt.DefaultView.ToTable();//绑定的其实是DefaultView//gvTestDataTable.DataSource = dt;//gvTestDataTable.DataBind();//判断一个字符串是否为DataTable的列名bool flag = dt.Columns.Contains("AX");
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