C#中sqlDataRead 的三种方式遍历读取各个字段数值的方法

数据库的查询分析器中写上如下代码：

create table studentname
(
 id int  primary key identity(1,1) not null ,
name nvarchar(500) not null
)
insert into studentname values('long')
insert into studentname values('long')
insert into studentname values('long')
insert into studentname values('long')
insert into studentname values('long')
insert into studentname values('chao')
insert into studentname values('chao')

--sql server 2012 通过。

---------------------------------------------------------------------------------------------------

以下是第一种方法：

using system.data;
 using system.data.sqlclient;
string constr = "server=localhost;uid=sa;pwd=longshicheng;database=student";
      sqlconnection conn = new sqlconnection(constr);
      sqlcommand cmd = new sqlcommand("select * from studentname", conn);
      conn.open();
      sqldatareader rdr = cmd.executereader();
      string makestr = "";
      datatable table = new datatable();
      table.load(rdr); //数据表装入 datareader 。
      string result="";
      for (int i = 0; i < table.rows.count; i++) // 遍历行
      {
        for (int j = 0; j < table.columns.count; j++) //遍历列
        {
          result += table.rows[i][j].tostring(); //逐行逐列显示每个单元格的数值。
        }
        result += environment.newline; //一行遍历完成就写入回车。
      }
      txtlab.text = result;
      /***************************************************************/

以下是第二种方法:         

string constr = "server=localhost;uid=sa;pwd=longshicheng;database=student";
      sqlconnection conn = new sqlconnection(constr);
      sqlcommand cmd = new sqlcommand("select * from studentname", conn);
      conn.open();
      sqldatareader rdr = cmd.executereader();
      string makestr = "";
      for (int k = 0; k < rdr.fieldcount; k++) //获取字段名称
      {
        makestr += rdr.getname(k) + "\t"; //载入字段名称
      }
      makestr += environment.newline; //换行
      makestr = makestr + "---------------------------------------------"+environment.newline;
      while (rdr.read()) //逐行读取每一笔记录
      {
        for (int t = 0; t < rdr.fieldcount; t++) //逐列读出
        {
          makestr = makestr + rdr[t].tostring() + "\t"; //累加每一行，也就是逐个字段读出对应的数值
        }
        makestr = makestr + environment.newline; //又一行
      }
      txtinfo.text = makestr;
      rdr.close(); //关闭
      conn.close();
    }

以下是第三种方法：

string constr = "server=localhost;uid=sa;pwd=longshicheng;database=student";
      sqlconnection conn = new sqlconnection(constr);
      sqlcommand cmd = new sqlcommand("select * from studentname", conn);
      conn.open();
      sqldatareader rdr = cmd.executereader();
      string makestr = "";
      for (int k = 0; k < rdr.fieldcount; k++) //获取字段名称
      {
        makestr += rdr.getname(k) + "\t"; //载入字段名称
      }
      makestr += environment.newline; //换行
      makestr = makestr + "---------------------------------------------" + environment.newline;
      while (rdr.read()) //逐行读取每一笔记录
      {
        makestr = makestr + rdr.getvalue(0) + " \t" + rdr.getvalue(1).tostring() + "\t";
        makestr = makestr + environment.newline;
      }
      txtother.text = makestr;
      rdr.close(); //关闭
      conn.close();

                    

  以上所有方法运行结果均如下：

id    name   
---------------------------------------------
1     long  
2     long    
3     long    
4     long     
5     long     
6     chao    
7     chao

总结

以上所述是小编给大家介绍的c#中sqldataread 的三种方式遍历读取各个字段数值的方法，希望对大家有所帮助