Question

我目前正在构建一个webform，它使用下拉列表和radiobuttonList等。有一些小的验证，如果你在这些元素中的任何一个上选择一个值，就必须有一个回发，并且可能必须重新加载某些元素，这取决于业务逻辑。现在我为RBL和DDL创建了eventHandlers，但是我遇到了问题。

如果我更改DDL上的值，则会触发回发并且程序循环通过我的方法，没问题。如果我更改RBL上的值，则不会触发回发，也不会触发。奇怪的是，如果我首先在RBL中更改某些内容然后在DDL中更改某些内容，它会以正确的顺序循环遍历两个事件处理程序。

但显然这对我来说并不理想。如果用户首先在RBL中更改了DDL中的某些内容，那么该程序将无法正常运行。

我将在下面发布我的代码，是否有人知道如何使RadioButtonList触发回发/事件处理程序？

C＃

protected void SchoolTypeID_Index_Changed(object sender, EventArgs e)
    {
        //code
    }

protected void ddlStudentenStad_IndexChanged(object sender, EventArgs e)
    {
        //code
    }

ASP.net

<asp:DropDownList ID="ddlStudentenStad" DataTextField="stad" DataValueField="id" AutoPostBack="true" 
OnSelectedIndexChanged="ddlStudentenStad_IndexChanged" runat="server" class="SelectDropDown"></asp:DropDownList>

<asp:RadioButtonList ID="rblSchoolType" runat="server" AutoPostBack="true" DataTextField="type" 
DataValueField="id" OnSelectedIndexChanged="SchoolTypeID_Index_Changed" RepeatDirection="Horizontal"/>

编辑：我们还制作了一个RadioButtonListAdapter类，因为我们过去在这个元素上遇到了更多问题。代码粘贴在下面，如果有人碰巧看到错误。

public class RadioButtonListControlAdapter：ControlAdapter {

public RadioButtonListControlAdapter()
{
}

protected override void Render(HtmlTextWriter writer)
{
    RadioButtonList ButtonList = Control as RadioButtonList;

    if (null != ButtonList)
    {
        int i = 0;

        if (ButtonList.RepeatDirection == RepeatDirection.Horizontal)
        {
            writer.WriteFullBeginTag("div class=\"row collapse\"");


            int aantalCols = (int)Math.Floor((double)12 / (double)ButtonList.Items.Count);
            foreach (ListItem li in ButtonList.Items)
            {
                string itemClientID = Helpers.GetListItemClientID(ButtonList, li);

                writer.WriteFullBeginTag("div class=\"large-" + aantalCols + " columns\" style=\"width:" + 100/ButtonList.Items.Count + "% !important; \"");

                writer.WriteFullBeginTag("label for=\"" + ButtonList.UniqueID + "\"");
                if (ButtonList.TextAlign == TextAlign.Right)
                {
                    RenderRadioButtonListInput(writer, ButtonList, li);
                    RenderRadioButtonListLabel(writer, ButtonList, li);
                }
                else
                {
                    RenderRadioButtonListLabel(writer, ButtonList, li);
                    RenderRadioButtonListInput(writer, ButtonList, li);
                }
                writer.WriteEndTag("label");

                writer.WriteEndTag("div");
                if (this.Page != null)
                    Page.ClientScript.RegisterForEventValidation(ButtonList.UniqueID, li.Value);
                //if (ButtonList.RepeatDirection == RepeatDirection.Vertical)
                //    writer.Write("<br />"); 
                writer.WriteLine();
            }

            writer.WriteEndTag("div");
            if (this.Page != null)
            {
                Page.ClientScript.RegisterForEventValidation(ButtonList.UniqueID);
            }
        }
        else
        {
            foreach (ListItem li in ButtonList.Items)
            {
                string itemClientID = Helpers.GetListItemClientID(ButtonList, li);
                //writer.WriteFullBeginTag("div class=\"row\"");
                writer.WriteFullBeginTag("label for=\"" + ButtonList.UniqueID + "\"");
                if (ButtonList.TextAlign == TextAlign.Right)
                {
                    RenderRadioButtonListInput(writer, ButtonList, li);
                    RenderRadioButtonListLabel(writer, ButtonList, li);
                }
                else
                {
                    RenderRadioButtonListLabel(writer, ButtonList, li);
                    RenderRadioButtonListInput(writer, ButtonList, li);
                }
                writer.WriteEndTag("label");
                //writer.WriteEndTag("div");

                if (this.Page != null)
                    Page.ClientScript.RegisterForEventValidation(ButtonList.UniqueID, li.Value);
                //if (ButtonList.RepeatDirection == RepeatDirection.Vertical)
                //    writer.Write("<br />"); 
                writer.WriteLine();
            }
        }


        if (this.Page != null)
            Page.ClientScript.RegisterForEventValidation(ButtonList.UniqueID);
    }
}

private void RenderRadioButtonListInput(HtmlTextWriter writer, RadioButtonList ButtonList, ListItem li)
{
    writer.AddAttribute(HtmlTextWriterAttribute.Id, Helpers.GetListItemClientID(ButtonList, li));
    writer.AddAttribute(HtmlTextWriterAttribute.Type, "radio");
    writer.AddAttribute(HtmlTextWriterAttribute.Name, ButtonList.UniqueID);
    writer.AddAttribute(HtmlTextWriterAttribute.Value, li.Value);

    writer.AddStyleAttribute(HtmlTextWriterStyle.Display, "none");
    writer.AddAttribute(HtmlTextWriterAttribute.Class, "hidden-field");
    if (li.Selected)
        writer.AddAttribute(HtmlTextWriterAttribute.Checked, "checked");
    if (li.Enabled == false || ButtonList.Enabled == false)
        writer.AddAttribute(HtmlTextWriterAttribute.Disabled, "disabled");
    if (li.Enabled == true && ButtonList.Enabled == true && ButtonList.AutoPostBack)
    {
        writer.AddAttribute(HtmlTextWriterAttribute.Onclick, String.Format(@"javascript:setTimeout('__doPostBack(\'{0}\',\'\')', 0)", Helpers.GetListItemUniqueID(ButtonList, li)));
    }
    writer.RenderBeginTag(HtmlTextWriterTag.Input);
    writer.RenderEndTag();
}

private void RenderRadioButtonListLabel(HtmlTextWriter writer, RadioButtonList ButtonList, ListItem li)
{
    writer.WriteFullBeginTag("span class=\"custom radio\"");
    writer.WriteEndTag("span");      
    writer.Write(" " + li.Text);

}

}

Answer 1

尝试使用更新面板包装控件。

您还可以浏览代码或发布更多详细信息。事件未触发的原因可能是一些额外的逻辑，未在代码清单中显示。我无法重现这个问题。

ASP.net w / C＃RadiobuttonList不会触发回发

1 个答案: