如何添加一個css類到ASP.Net的更新面板？

Question

如何添加一個css類到c＃代碼後面的c＃代碼中的更新面板

Answer 1

正如你所看到的更新面板沒有CSS類屬性。所以既然不能直接完成，你需要一個解決方法;有兩個（從UpdatePanel and CSS抓取），可以得到你想要的行爲。

一是圍繞更新面板採用了DIV：

<div id="foo" style="visibility: hidden; position: absolute"> 
    <asp:UpdatePanel ID="UpdatePanel1" runat="server"> 
    </asp:UpdatePanel> 
</div> 

另一種是應用基於更新面板ID的CSS選擇：

<style type="text/css"> 
#<%=UpdatePanel1.ClientID%> { 
    visibility: hidden; 
    position: absolute; 
} 
</style> 

另一種方式中未提及該文章圍繞面板中的一個div和樣式更新面板基於它呈現爲一個div：

<style type="text/css"> 
#foo div { 
    visibility: hidden; 
    position: absolute; 
} 
</style> 

<div id="foo"> 
    <asp:UpdatePanel ID="UpdatePanel1" runat="server"> 
    </asp:UpdatePanel> 
</div> 

Answer 2

更新面板可以呈現爲div或跨度（取決於模式）。達到你想要的最簡單方法是包裹在UpdatePanel標準面板：

<asp:Panel ID="Panel1" runat="Server"> 
    <asp:UpdatePanel ID="UpdatePanel1" runat="server"> 
    </asp:UpdatePanel> 
</asp:Panel> 

的你可以做到這一點的代碼隱藏：

Panel1.CssClass = "myCssClass"; 

你也可以使用一個div，像LFSR諮詢說，並添加runat="server"，然後更改類屬性。但面板更容易處理（面板只是呈現爲div）。

Answer 3

你可以使用一個類HTML屬性

<asp:UpdatePanel ID="UpdatePanel1" runat="server" class="MyCssClass"> 
</asp:UpdatePanel> 

Answer 4

你也可以做，因爲我已經和剛剛創建一個繼承UpdatePanel的一個新的類。我得到了這個地方的基礎，但我不記得在哪裏，所以我不能完全信任，但我只是調整了這個想法。我將爲HTML屬性執行相同的操作（因爲.attributes（）集合用於UpdatePanel上的css而不是像大多數其他web.ui.controls一樣是原始HTML屬性）。

更新：我已經更新，包括一些其他的自定義，我已經允許添加任何屬性。真的這複製了第一個定製，除了第一個創建一個相當標準的方法，這是完全靈活的（因此不標準）。經由http://www.developerfusion.com/

Imports System.ComponentModel 
Imports System.Collections 
Imports System.Web.UI   

Namespace Controls 

    Public Class UpdatePanelCss 
     Inherits UpdatePanel 
     Private _cssClass As String 
     Private _tag As HtmlTextWriterTag = HtmlTextWriterTag.Div 
     Public HtmlAttributes As New HtmlAttributes 

     <DefaultValue("")> _ 
     <Description("Applies a CSS style to the panel.")> _ 
     Public Property CssClass() As String 
      Get 
       Return If(_cssClass, [String].Empty) 
      End Get 
      Set(ByVal value As String) 
       _cssClass = value 
      End Set 
     End Property 

     ' Hide the base class's RenderMode property since we don't use it 
     <Browsable(False)> _ 
     <EditorBrowsable(EditorBrowsableState.Never)> _ 
     <DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)> _ 
     Public Shadows Property RenderMode() As UpdatePanelRenderMode 
      Get 
       Return MyBase.RenderMode 
      End Get 
      Set(ByVal value As UpdatePanelRenderMode) 
       MyBase.RenderMode = value 
      End Set 
     End Property 

     <DefaultValue(HtmlTextWriterTag.Div)> _ 
     <Description("The tag to render for the panel.")> _ 
     Public Property Tag() As HtmlTextWriterTag 
      Get 
       Return _tag 
      End Get 
      Set(ByVal value As HtmlTextWriterTag) 
       _tag = value 
      End Set 
     End Property 

     Protected Overrides Sub RenderChildren(ByVal writer As HtmlTextWriter) 
      If IsInPartialRendering Then 
       ' If the UpdatePanel is rendering in "partial" mode that means 
       ' it's the top-level UpdatePanel in this part of the page, so 
       ' it doesn't render its outer tag. We just delegate to the base 
       ' class to do all the work. 
       MyBase.RenderChildren(writer) 
      Else 
       ' If we're rendering in normal HTML mode we do all the new custom 
       ' rendering. We then go render our children, which is what the 
       ' normal control's behavior is. 
       writer.AddAttribute(HtmlTextWriterAttribute.Id, ClientID) 
       If CssClass.Length > 0 Then 
        writer.AddAttribute(HtmlTextWriterAttribute.[Class], CssClass) 
       End If 
       If HtmlAttributes.Count > 0 Then 
        For Each ha As HtmlAttribute In HtmlAttributes 
         writer.AddAttribute(ha.AttrName, ha.AttrVal) 
        Next 
       End If 
       writer.RenderBeginTag(Tag) 
       For Each child As Control In Controls 
        child.RenderControl(writer) 
       Next 
       writer.RenderEndTag() 
      End If 
     End Sub 

    End Class 

    Public Class HtmlAttribute 
     Private PAttrName As String 
     Private PAttrVal As String 

     Public Sub New(AttrName As String, AttrVal As String) 
      PAttrName = AttrName 
      PAttrVal = AttrVal 
     End Sub 

     Public Property AttrName() As String 
      Get 
       Return PAttrName 
      End Get 
      Set(value As String) 
       PAttrName = value 
      End Set 
     End Property 

     Public Property AttrVal() As String 
      Get 
       Return PAttrVal 
      End Get 
      Set(value As String) 
       PAttrVal = value 
      End Set 
     End Property 

    End Class 


    Public Class HtmlAttributes 
     Inherits CollectionBase 

     Public ReadOnly Property Count() As Integer 
      Get 
       Return List.Count 
      End Get 
     End Property 

     Default Public Property Item(ByVal index As Integer) As HtmlAttribute 
      Get 
       Return CType(List.Item(index), HtmlAttribute) 
      End Get 
      Set(ByVal Value As HtmlAttribute) 
       List.Item(index) = Value 
      End Set 
     End Property 

     Public Function Add(ByVal item As HtmlAttribute) As Integer 
      Return List.Add(item) 
     End Function 

     Public Sub Remove(ByVal index As Integer) 
      If index < List.Count AndAlso List.Item(index) IsNot Nothing Then 
       List.RemoveAt(index) 
      Else 
       Throw New Exception(String.Concat("Index(", index.ToString, ") is not valid. List only has ", List.Count.ToString, " items.")) 
      End If 
     End Sub 

     Public Sub Remove(ByRef hAttribute As HtmlAttribute) 
      If List.Count > 0 AndAlso List.IndexOf(hAttribute) >= 0 Then 
       List.Remove(hAttribute) 
      Else 
       Throw New Exception("Object does not exist in collection.") 
      End If 
     End Sub 

    End Class 


End Namespace 

C＃轉換：

using Microsoft.VisualBasic; 
using System; 
using System.Collections; 
using System.Collections.Generic; 
using System.Data; 
using System.Diagnostics; 
using System.ComponentModel; 
using System.Web.UI; 

namespace Controls 
{ 

    public class UpdatePanelCss : UpdatePanel 
    { 
     private string _cssClass; 
     private HtmlTextWriterTag _tag = HtmlTextWriterTag.Div; 

     public HtmlAttributes HtmlAttributes = new HtmlAttributes(); 
     [DefaultValue("")] 
     [Description("Applies a CSS style to the panel.")] 
     public string CssClass { 
      get { return _cssClass ?? String.Empty; } 
      set { _cssClass = value; } 
     } 

     // Hide the base class's RenderMode property since we don't use it 
     [Browsable(false)] 
     [EditorBrowsable(EditorBrowsableState.Never)] 
     [DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)] 
     public new UpdatePanelRenderMode RenderMode { 
      get { return base.RenderMode; } 
      set { base.RenderMode = value; } 
     } 

     [DefaultValue(HtmlTextWriterTag.Div)] 
     [Description("The tag to render for the panel.")] 
     public HtmlTextWriterTag Tag { 
      get { return _tag; } 
      set { _tag = value; } 
     } 

     protected override void RenderChildren(HtmlTextWriter writer) 
     { 
      if (IsInPartialRendering) { 
       // If the UpdatePanel is rendering in "partial" mode that means 
       // it's the top-level UpdatePanel in this part of the page, so 
       // it doesn't render its outer tag. We just delegate to the base 
       // class to do all the work. 
       base.RenderChildren(writer); 
      } else { 
       // If we're rendering in normal HTML mode we do all the new custom 
       // rendering. We then go render our children, which is what the 
       // normal control's behavior is. 
       writer.AddAttribute(HtmlTextWriterAttribute.Id, ClientID); 
       if (CssClass.Length > 0) { 
        writer.AddAttribute(HtmlTextWriterAttribute.Class, CssClass); 
       } 
       if (HtmlAttributes.Count > 0) { 
        foreach (HtmlAttribute ha in HtmlAttributes) { 
         writer.AddAttribute(ha.AttrName, ha.AttrVal); 
        } 
       } 
       writer.RenderBeginTag(Tag); 
       foreach (Control child in Controls) { 
        child.RenderControl(writer); 
       } 
       writer.RenderEndTag(); 
      } 
     } 

    } 

    public class HtmlAttribute 
    { 
     private string PAttrName; 

     private string PAttrVal; 
     public HtmlAttribute(string AttrName, string AttrVal) 
     { 
      PAttrName = AttrName; 
      PAttrVal = AttrVal; 
     } 

     public string AttrName { 
      get { return PAttrName; } 
      set { PAttrName = value; } 
     } 

     public string AttrVal { 
      get { return PAttrVal; } 
      set { PAttrVal = value; } 
     } 

    } 


    public class HtmlAttributes : CollectionBase 
    { 

     public int Count { 
      get { return List.Count; } 
     } 

     public HtmlAttribute this[int index] { 
      get { return (HtmlAttribute)List[index]; } 
      set { List[index] = value; } 
     } 

     public int Add(HtmlAttribute item) 
     { 
      return List.Add(item); 
     } 

     public void Remove(int index) 
     { 
      if (index < List.Count && List[index] != null) { 
       List.RemoveAt(index); 
      } else { 
       throw new Exception(string.Concat("Index(", index.ToString(), ") is not valid. List only has ", List.Count.ToString(), " items.")); 
      } 
     } 

     public void Remove(ref HtmlAttribute hAttribute) 
     { 
      if (List.Count > 0 && List.IndexOf(hAttribute) >= 0) { 
       List.Remove(hAttribute); 
      } else { 
       throw new Exception("Object does not exist in collection."); 
      } 
     } 

    } 


} 

Answer 5

HTML

<asp:UpdatePanel ID="UpdatePanel1" runat="server"></asp:UpdatePanel> 

CSS

<style type="text/css"> 
    #UpdatePanel1 { position: relative; } 
</style> 

Answer 6

代碼隱藏：

UpdatePanel panel = new UpdatePanel(); 

panel.Attributes.Add("class","your-css-class"); 

HTML結果：

<div id="..." class="your-css-class"></div>