DropDownList绑定及修改

一、DropDownList:

1、选项值保存到数据库：

   Hashtable ht=new Hashtable();//这里用Hashtable

   ht.Add("字段名"，DropDownListID.SelectedItem.Text.ToString());//保存选项Text

   ht.Add("字段名"，DropDownListID.SelectedItem.Value.ToString());//保存选项Value



2、选项值由数据库绑定到DropDownList：

   首先DropDownListID.ClearSelection();//清除选项

    DropDownListID.Items.FindByText(dr["字段名"].ToString()).Selected = true;//选项Text

    DropDownListID.Items.FindByValue(dr["字段名"].ToString()).Selected = true;//选项Value



二、RadioButtonList:

1、选项值保存到数据库(同DropDownList)：

   Hashtable ht=new Hashtable();//这里用Hashtable

   ht.Add("字段名"，RadioButtonListID.SelectedItem.Text.ToString());//保存选项Text

   ht.Add("字段名"，RadioButtonListID.SelectedItem.Value.ToString());//保存选项Value



2、选项值由数据库绑定到RadioButtonList

   string SelectItem = dr["字段名"].ToString();//将数据库中的选项值从DataRow中读出赋给变量SelectItem

   for (int i = 0; i < RadioButtonListID.Items.Count; i++)

   {//用for循环判断那项被选种

       if (RadioButtonListID.Items[i].Text == SelectItem)RadioButtonListID.Items[i].Selected = true;

   }



三、CheckBoxList:

1、选项值保存到数据库

   string SelectItem = "";//声明一个变量来接受选项

   for (int i = 0; i < CheckBoxListID.Items.Count; i++)

   {//用for循环将所有选项用","隔开连接起来

        if (CheckBoxListID.Items[i].Selected)

        {

            SelectItem = SelectItem + CheckBoxListID.Items[i].Value + ",";//选项后加","隔开

        }

   }

   ht.Add("字段名",SelectItem.ToString());



2、选项值由数据库绑定到CheckBoxList

   string SelectItem = dr["字段名"].ToString();

   string[] arrStr = SelectItem.Split(',');//字段是以","隔开

   foreach (string str in arrStr)

   {

       for (int i = 0; i <CheckBoxListID.Items.Count; i++)

       {

          if (this.CheckBoxListID.Items[i].Value == str)

          {

             this.CheckBoxListID.Items[i].Selected = true;

          }

       }

   }

=================================================

1.把数据绑定到CheckBoxList中



  protected void Page_Load(object sender, EventArgs e)

        {

            if (!Page.IsPostBack)

            {

                SqlConnection con = GetDBCon.GetCon();

                con.Open();

                SqlDataAdapter sda = new SqlDataAdapter("select * from admin", con);

                DataSet ds = new DataSet();

                sda.Fill(ds,"admin");

                this.CheckBoxList1.DataSource = ds.Tables[0];

                this.CheckBoxList1.DataTextField = "username";//绑定的字段名

                this.CheckBoxList1.DataValueField = "userid";//绑定的值

                this.CheckBoxList1.DataBind();

               

             

                

            }

        }



2.循环读取出来



 protected void CheckBoxList1_SelectedIndexChanged(object sender, EventArgs e)

        {

            this.Lab2.Text = "";

            for (int i = 0; i < CheckBoxList1.Items.Count; i++)

            {

                if (this.CheckBoxList1.Items[i].Selected)

                {

                    this.Lab2.Text = this.Lab2.Text+CheckBoxList1.Items[i].Text+".";

                }

            }

        }