遍历ComboBox的内容

// 一：
for (int i = 0; i < comboBox1.Items.Count; i++)
{
    MessageBox.Show(comboBox1.GetItemText(comboBox1.Items[i]));
}

//二：
foreach (System.Data.DataRowView dr in comboBox1.Items)
{
    string id = dr["student_id"].ToString();
    string nane = dr["student_name"].ToString();
}

//for (int i = 0; i < comboBox1.Items.Count; i++)
//{
//    DataRowView dr = (DataRowView)comboBox1.Items[i];
//    string id = dr["student_id"].ToString();
//    string nane = dr["student_name"].ToString();
//}

//三：

for (int i = 0; i < comboBox1.Items.Count; i++)
{
    comboBox1.SelectedIndex = i;
    string value = comboBox1.SelectedValue.ToString();
}