javascript - 如何在从代码隐藏显示之前在弹出窗口中选择预填充的下拉列表选项

Question

此行将所选索引设置为正确的数字:

    ddlCliNewMsg.SelectedIndex = ddlCliNewMsg.Items.IndexOf(ddlCliNewMsg.Items.FindByValue(dr["ClientText"].ToString()));

但是当弹出窗口加载时，索引 0 被选中。

Answer 1

改变

    if (dr["ClientText"].ToString().Length > 0)
    {
    ddlCliNewMsg.SelectedValue = dr["ClientText"].ToString();
    }

到

    if (dr["ClientText"].ToString().Length > 0)
    {
    ddlCliNewMsg.ClearSelection(); //making sure the previous selection has been cleared
    ddlCliNewMsg.Items.FindByValue(dr["ClientText"].ToString()).Selected = true;
    }