ASP.NET與數據庫相關技巧

    一取得數據表 i 行 j 列的值

//建立並打開數據庫連接 

OleDbConnection conn=new OleDbConnection(); 

connConnectionString=strConnectionString;//strConnectionString為數據庫連接字符串 

connOpen(); 



string sql=select * from NewsClass order by ClassId desc; 

string x; 

DataSet ds=new DataSet(); 

OleDbDataAdapter da=new OleDbDataAdapter(sqlconn); 

daFill(dsNewsTable); 

DataTable dt=dsTables[NewsTable]; 

x=dtRows[i][]ToString()//數據表i行j列的值 

connclose(); 

    二將數據讀入DropDownList 

    （）DropDownList中添加數據

//建立並打開數據庫連接 

OleDbConnection conn=new OleDbConnection(); 

connConnectionString=strConnectionString;//strConnectionString為數據庫連接字符串 

connOpen(); 



string sql=select * from NewsClass order by ClassId desc; 

//建立數據集 

DataSet ds=new DataSet(); 

OleDbDataAdapter da=new OleDbDataAdapter(sqlconn); 

daFill(dsNewsTable); 

thisDropDownListDataSource=ds; 

thisDropDownListDataTextField = ClassName;//Text值 

thisDropDownListDataValueField = ClassID;//Value值 

thisDropDownListDataBind(); 



connClose(); 

    （）選中DropDownList的某項

thisDropDownListItemsFindByValue(dr[ClassID]ToString()Trim())Selected=true;
//dr為DataRow 

三分類編碼檢索出相應的分類名稱並在DataGrid中顯示 

（）ASPX中的代碼（ClassID為分類編碼）

<asp:TemplateColumn HeaderText=類 別> 

<ItemTemplate> 

<asp:Label id=lblClass runat=server 
Text=<%# GetClassName(ConvertToInt(DataBinderEval(Container 
DataItemClassID))) %>> 

</asp:Label> 

</ItemTemplate> 

</asp:TemplateColumn> 

（）C#代碼

/// 
 

/// 分類列根據數字返回文字 

/// 
 

///  

///  

public string GetClassName(int ClassID) 

{ 

OleDbConnection conn=new OleDbConnection(); 

connConnectionString=strConnectionString; 

connOpen(); 



string sql=select * from NewsClass where ClassID=+ClassID; 

DataSet ds=new DataSet(); 

OleDbDataAdapter da=new OleDbDataAdapter(sqlconn); 

daFill(dsClassTable); 

DataTable dt=dsTables[ClassTable]; 

string strClassName=dtRows[][ClassName]ToString(); 

connClose(); 



return strClassName;//返回 ClassID對應的ClassName 

} 

From:http://tw.wingwit.com/Article/program/net/201311/15348.html