一、取得数据表i行j列的值

//建立并打开数据库连接

OleDbConnectionconn=newOleDbConnection();

conn.ConnectionString=strConnectionString;//strConnectionString为数据库连接字符串

conn.Open();

stringsql="select*fromNewsClassorderbyClassIddesc";

stringx;

DataSetds=newDataSet();

OleDbDataAdapterda=newOleDbDataAdapter(sql,conn);

da.Fill(ds,"NewsTable");

DataTabledt=ds.Tables["NewsTable"];

x=dt.Rows[i][1].ToString()//数据表i行j列的值

conn.close();

二、将数据读入DropDownList

（1）DropDownList中添加数据

//建立并打开数据库连接

OleDbConnectionconn=newOleDbConnection();

conn.ConnectionString=strConnectionString;//strConnectionString为数据库连接字符串

conn.Open();

stringsql="select*fromNewsClassorderbyClassIddesc";

//建立数据集

DataSetds=newDataSet();

OleDbDataAdapterda=newOleDbDataAdapter(sql,conn);

da.Fill(ds,"NewsTable");

this.DropDownList1.DataSource=ds;

this.DropDownList1.DataTextField="ClassName";//Text值

this.DropDownList1.DataValueField="ClassID";//Value值

this.DropDownList1.DataBind();

conn.Close();

（2）选中DropDownList的某项

this.DropDownList1.Items.FindByValue(dr["ClassID"].ToString().Trim()).Selected=true;//dr为DataRow

三、分类编码检索出相应的分类名称并在DataGrid中显示

（1）.ASPX中的代码（ClassID为分类编码）：

<asp:TemplateColumnHeaderText="类别">

<ItemTemplate>

<asp:Labelid=lblClassrunat="server"Text='<%#GetClassName(Convert.ToInt32(DataBinder.Eval(Container,"DataItem.ClassID")))%>'>

</asp:Label>

</ItemTemplate>

</asp:TemplateColumn>

（2）C#代码：

///<summary>

///"分类"列根据数字返回文字

///</summary>

///<paramname="IsPassed"></param>

///<returns></returns>

publicstringGetClassName(intClassID)

{

OleDbConnectionconn=newOleDbConnection();

conn.ConnectionString=strConnectionString;

conn.Open();

stringsql="select*fromNewsClasswhereClassID="+ClassID;

DataSetds=newDataSet();

OleDbDataAdapterda=newOleDbDataAdapter(sql,conn);

da.Fill(ds,"ClassTable");

DataTabledt=ds.Tables["ClassTable"];

stringstrClassName=dt.Rows[0]["ClassName"].ToString();

conn.Close();

returnstrClassName;//返回ClassID对应的ClassName

}