asp.NetDropDownList 3級連動ドロップダウンメニュー実装コード

 
  
if (!IsPostBack) 
  
{ 
  
//       
  
this.DropDownList1.DataSource = dsbb.SelectSubjct1(); 
  
this.DropDownList1.DataTextField = "cName"; 
  
this.DropDownList1.DataValueField = "Ccode"; 
  
this.DropDownList1.DataBind(); 
  
this.DropDownList1.Items.Insert(0,new ListItem("       ","0")); 
  
this.DropDownList8.Items.Insert(0, new ListItem("       ", "0")); 
  
this.DropDownList9.Items.Insert(0,new ListItem ("       ","0")); 
  
//       
  
 
  
} 
  
/// 
 
  
///        
  
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///  
  
protected void DropDownList1_SelectedIndexChanged(object sender, EventArgs e) 
  
{ 
  
libs.Database.Dbbase dbb = new libs.Database.Dbbase(); 
  
if (Convert.ToInt32(this.DropDownList1.SelectedValue) == 0) //       
  
{ 
  
this.DropDownList8.Items.Clear(); 
  
this.DropDownList8.Items.Insert(0, new ListItem("       ", "0")); 
  
this.DropDownList9.Items.Clear(); 
  
this.DropDownList9.Items.Insert(0, new ListItem("       ", "0")); 
  
} 
  
else //       
  
{ 
  
this.DropDownList8.DataSource = dbb.Selectsubjct2(this.DropDownList1.SelectedValue.Substring(0,2)); 
  
this.DropDownList8.DataTextField = "cName"; 
  
this.DropDownList8.DataValueField = "Ccode"; 
  
this.DropDownList8.DataBind(); 
  
this.DropDownList8.Items.Insert(0,new ListItem ("       ","0")); 
  
this.DropDownList9.Items.Clear();//       
  
this.DropDownList9.Items.Insert(0, new ListItem("       ", "0")); 
  
} 
  
} 
  
/// 
 
  
///        
  
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///  
  
protected void DropDownList8_SelectedIndexChanged(object sender, EventArgs e) 
  
{ 
  
libs.Database.Dbbase dbase = new libs.Database.Dbbase(); 
  
this.DropDownList9.DataSource = dbase.selectsubject3(this.DropDownList8.SelectedValue.Substring(0,4)); 
  
this.DropDownList9.DataTextField = "cName"; 
  
this.DropDownList9.DataValueField = "Ccode"; 
  
this.DropDownList9.DataBind(); 
  
this.DropDownList9.Items.Insert(0,new ListItem("       ","0")); 
  
} 
  
 
 

 
  
/// 
 
  
///        
  
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///  
  
public DataSet SelectSubjct1() 
  
{ 
  
string con = System.Configuration.ConfigurationSettings.AppSettings["sqlconn"]; 
  
SqlConnection conn = new SqlConnection(con); 
  
string sqlstr = "SELECT kndid, Ccode, cName, cLevel FROM kind WHERE cLevel = 1"; 
  
DataSet dst = new DataSet(); 
  
SqlDataAdapter sda = new SqlDataAdapter(sqlstr,conn); 
  
try 
  
{ 
  
sda.Fill(dst); 
  
return dst; 
  
} 
  
catch (Exception ex) 
  
{ 
  
throw new Exception(ex.Message); 
  
} 
  
finally 
  
{ 
  
conn.Close(); 
  
} 
  
} 
  
/// 
 
  
///          
  
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///  
  
///  
  
public DataSet Selectsubjct2(string ccode) 
  
{ 
  
string conn1 = System.Configuration.ConfigurationSettings.AppSettings["sqlconn"]; 
  
SqlConnection conn = new SqlConnection(conn1); 
  
string sqqq = "select kndid,Ccode,cName,cLevel from kind where cLevel = 2 and Ccode like '" + ccode + "%'"; 
  
DataSet dss = new DataSet(); 
  
SqlDataAdapter sdd = new SqlDataAdapter(sqqq,conn); 
  
try 
  
{ 
  
sdd.Fill(dss); 
  
return dss; 
  
} 
  
catch (Exception ex) 
  
{ 
  
throw new Exception(ex.Message); 
  
} 
  
finally 
  
{ 
  
conn.Close(); 
  
} 
  
} 
  
/// 
 
  
///          
  
/// 
 
  
///  
  
///  
  
public DataSet selectsubject3(string cde) 
  
{ 
  
string conn2 = System.Configuration.ConfigurationSettings.AppSettings["sqlconn"]; 
  
SqlConnection conn = new SqlConnection(conn2); 
  
string sqq = "select kndid,Ccode,cName,cLevel from kind where cLevel = 3 and Ccode like '" + cde + "%'"; 
  
DataSet dst = new DataSet(); 
  
SqlDataAdapter sdaa = new SqlDataAdapter(sqq,conn); 
  
try 
  
{ 
  
sdaa.Fill(dst); 
  
return dst; 
  
} 
  
catch (Exception ex) 
  
{ 
  
throw new Exception(ex.Message); 
  
} 
  
finally 
  
{ 
  
conn.Close(); 
  
} 
  
}