1  string sql = "select distinct RoleName from tb_Role";
 2             DataTable dt = SqlHelper.DataTable(sql);
 3             cmb_Authority.Items.Clear();//移除下拉框中所有集合
 4             foreach (DataRow dr in dt.Rows)//遍歷數(shù)據(jù)表中行的數(shù)據(jù)
 5             {
 6                 cmb_Authority.Items.Add(dr[0]);//把表中第一列的數(shù)據(jù)添加到下拉框中
 7             }
 8             if (xiu==0)
 9             {               
10                 cmb_Authority.SelectedIndex = 0;
11             }
12             if (xiu==1)
13             {
14                 btn_Reg.Text = "修改";
15                 txt_OperatorName.Text = tb_users.OperatorName;
16                 txt_UserName.Text = tb_users.UserName;
17                 txt_UserName.ReadOnly = true;
18                 txt_Pwd.Text = tb_users.Pwd;
19                 cmb_Authority.Items.Clear();//移除下拉框中所有集合
20                 cmb_Authority.Items.Add(tb_users.RoleName);
21                 cmb_Authority.SelectedIndex = 0;
22                 foreach (DataRow dr in dt.Rows)//遍歷數(shù)據(jù)表中行的數(shù)據(jù)
23                 {
24                     if (dr[0].ToString()== tb_users.RoleName)
25                     {
26                         continue;
27                     }
28                     cmb_Authority.Items.Add(dr[0]);//把表中第一列的數(shù)據(jù)添加到下拉框中
29                 }
30 
31             }

 1 string sql = "select * from tb_Role"; //查詢數(shù)據(jù)所有信息
 2             DataTable dt = SqlHelper.DataTable(sql);
 3             cmb_Authority.DataSource = dt; //下拉框數(shù)據(jù)源為dt
 4             cmb_Authority.DisplayMember = "RoleName";//顯示成員
 5             cmb_Authority.ValueMember = "RoleID"; //值成員(類似與索引)
 6 
 7             //cmb_Authority.Items.Clear();//移除下拉框中所有集合
 8             //foreach (DataRow dr in dt.Rows)//遍歷數(shù)據(jù)表中行的數(shù)據(jù)
 9             //{
10             //    cmb_Authority.Items.Add(dr[0]);//把表中第一列的數(shù)據(jù)添加到下拉框中
11             //}
12             //if (xiu==0)
13             //{               
14             //    cmb_Authority.SelectedIndex = 0;
15             //}
16             if (xiu==1)
17             {
18                 btn_Reg.Text = "修改";
19                 txt_OperatorName.Text = tb_users.OperatorName;
20                 txt_UserName.Text = tb_users.UserName;
21                 txt_UserName.ReadOnly = true;
22                 txt_Pwd.Text = tb_users.Pwd;
23                 cmb_Authority.SelectedValue = tb_users.RoleID; //(下拉框的值=這個(gè)索引)
24             }

            comboBox1.Items.Add(new { key = "key", value = "value" });

            ArrayList list = new ArrayList();
            list.Add(new DictionaryEntry("name", "姓名"));
            list.Add(new DictionaryEntry("username", "用戶名"));
            list.Add(new DictionaryEntry("sfz", "身份Y證號(hào)"));
            list.Add(new DictionaryEntry("Tel", "電話號(hào)碼"));
            comboBox1.DataSource = list;
            comboBox1.DisplayMember = "Value";//顯示出來的。Text
            comboBox1.ValueMember = "Key";// value值。