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在下拉列表中动态添加值

drop-down-menu asp.net

hud · 技术社区 · 10 年前

我有一个州和市的下拉列表。当用户从第一个下拉列表中选择任何状态时,城市将反映在另一个下拉列表。我在城市下拉列表中给出了OTHER选项。以便用户可以为相应的添加添加自己的城市。在这里,默认情况下文本框是隐藏的,当用户从城市下拉列表中选择OTHER选项时,它是可见的。我希望文本框值插入下拉列表中。我尝试使用下面的代码和帮助按钮,但它不适用于我。请查看代码。

 protected void ddlLocation_SelectedIndexChanged(object sender, EventArgs e)
{
    if (ddlLocation.SelectedItem.Text == "Other")
    {
        txtOtherCity.Visible = true;
    }
    else {
        txtOtherCity.Visible = false;
    }
}
protected void btnAddDropDown_Click(object sender, EventArgs e)
{
    conn = new SqlConnection();
    try
    {
        conn.Open();
        if (txtOtherCity.Text != "")
        {
            ddllocation1.Items.Insert(0, txtOtherCity.Text);
            txtOtherCity.Text = "";
        }
        string commandtext = "Insert into Career.Job Values('" + txtOtherCity.Text.Trim() + "') where Location='" + ddllocation1.SelectedItem.Text + "'";
        SqlCommand cmd = new SqlCommand(commandtext);
        cmd.CommandType = CommandType.Text;
        cmd.ExecuteNonQuery();
        conn.Close();
    }
    catch (Exception ex)
    {
        Response.Write(ex.Message);//You Can Haave Messagebox here
    }
    finally
    {
        conn.Close();
    }
}

此外,请参见下拉列表、文本框和按钮的html代码

  <tr>
    <td class="td">Location/City</td>
    <td>
        <asp:dropdownlist cssclass="txtfld-popup" id="ddlLocation" runat="server" autopostback="true" onselectedindexchanged="ddlLocation_SelectedIndexChanged"></asp:dropdownlist>
        <asp:requiredfieldvalidator cssclass="error_msg" id="reqLocation" controltovalidate="ddlLocation" runat="server" errormessage="Please enter location" initialvalue="--Select--" setfocusonerror="true"></asp:requiredfieldvalidator>
    </td>
</tr>
<tr>
    <td>
        <asp:textbox id="txtOtherCity" runat="server" visible="false" cssclass="txtfld-popup"></asp:textbox>
        &nbsp;&nbsp;&nbsp;
                    <asp:button id="btnAddDropDown" runat="server" width="63" text="Add" causesvalidation="false" />
    </td>
</tr>

请帮忙。

1 回复 | 直到 10 年前

hud 10 年前

我这样加了它,效果很好。

  protected void ddlLocation_SelectedIndexChanged(object sender, EventArgs e)
{
    if (ddlLocation.SelectedItem.Text == "Other")
    {
        txtOtherCity.Visible = true;
    }
    else {
        txtOtherCity.Visible = false;
    }
}
protected void btnAddDropDown_Click1(object sender, EventArgs e)
{
    string city = txtOtherCity.Text.Trim();
    if (!string.IsNullOrEmpty(city))
    {
        ddlLocation.Items.Add(new ListItem(city, city));
    }
}