我有一个我意识到的非常基本的问题,我试图在选定的索引更改时从 DropDownList 的选定值返回一个字符串值,但由于某种或其他原因它没有发生。
protected void drpMinisters_SelectedIndexChanged(object sender, EventArgs e)
{
name = drpMinisters.SelectedValue;
LabMessage.Text = name;
}
当我尝试将名称添加到数据库时,我得到一个 NullReferenceException。
protected void butSubmitMinister_Click(object sender, EventArgs e)
{
int index = drpMinisters.SelectedIndex;
if (index == 0)
{
LabMessage.Text = "Please select a minister";
return;
}
try
{
OleDbCommand cmd = conn.CreateCommand();
cmd.CommandText = @"INSERT INTO MinisterTable(MinisterName)VALUES(" + name + "')";
cmd.ExecuteNonQuery();
LabMessage.Text = "The record was successfully added";
conn.Close();
}
catch (Exception ex)
{
LabMessage.Text = ex.ToString();
}
}
建议也许。