动态绑定方法一：动态绑定数据库中的字段。

动态绑定方法一：动态绑定数据库中的字段。

SqlConnection conn = UtilitySqlClass.OperateDataBase.ReturnConn();

string strSQL = "select * from CompanyType";

SqlDataAdapter ada = new SqlDataAdapter(strSQL, conn);

DataSet ds = new DataSet();

ada.Fill(ds, "CompanyType");

DropDownList1.DataSource = ds.Tables["CompanyType"].DefaultView;

DropDownList1.DataValueField = ds.Tables["CompanyType"].Columns[1].ColumnName;

DropDownList1.DataTextField = ds.Tables["CompanyType"].Columns[1].ColumnName;

DropDownList1.DataBind();

ds.Dispose();

动态绑定方法二：利用DropDownList.Items.Add方法。

protected void Page_Load(object sender, EventArgs e)
{

if (!IsPostBack)
{
SqlConnection conn = UtilitySqlClass.OperateDataBase.ReturnConn();
try
{
conn.Open();

this.DropDownList1.Items.Add("");

string strSQL = "select CompanyType from CompanyType";

SqlCommand com = new SqlCommand(strSQL, conn);
SqlDataReader dr = com.ExecuteReader();

while (dr.Read())
{

this.DropDownList1.Items.Add(dr["CompanyType"].ToString());
}
}

catch (Exception ex)
{

Response.Write("<scirpt>alert('" + ex.Message.ToString() + "')</script>");
}
finally
{
conn.Close();
}
}
}

string ConnString = ConfigurationSettings.AppSettings["ConnectionString"];

    //创建一个SqlConnection

    SqlConnection Conn = new SqlConnection( ConnString );    

    string SQL_Select = "select id, ItemName from DDLItem order by id desc";

    //构造一个SqlDataAdapter

    SqlDataAdapter myAdapter = new SqlDataAdapter( SQL_Select, Conn);

    //开始读取数据

    Conn.Open();

    DataSet dataSet = new DataSet();

    myAdapter.Fill( dataSet,"Table1" );

    Conn.Close();

    //开始绑定DropDownList

    //指定DropDownList使用的数据源

    DropDownList1.DataSource = dataSet.Tables["Table1"].DefaultView;

    //指定DropDownList使用的表里的那些字段

    DropDownList1.DataTextField = "ItemName"; //dropdownlist的Text的字段

    DropDownList1.DataValueField = "id";//dropdownlist的Value的字段

    DropDownList1.DataBind();
 
con.Open();

    SqlCommand cmd = new SqlCommand(strSql,con);

    SqlDataReader dr = cmd.ExecuteReader();

    while (dr.Read())

    {   

      DropDownList1.Items.Add(new ListItem(dr["status"].ToString(), dr["status_Id"].ToString()));

    }