如何使用样式占位符和样式控件控制ASP.NET主题中的样式表
更新：这篇文章变成了一篇博客文章，上面有更新的链接和代码，在我的博客上：如何使用样式占位符和样式控件控制ASP.NET主题中的样式表,asp.net,css,themes,custom-server-controls,Asp.net,Css,Themes,Custom Server Controls,更新：这篇文章变成了一篇博客文章，上面有更新的链接和代码，在我的博客上： 问题很简单。当使用ASP.NET主题时，您对如何将样式表呈现到页面上没有多少发言权 渲染引擎使用链接.Href.StartsWith（themePath））.ToList（）按字母顺序添加主题文件夹中的所有样式表； //删除自动添加的样式表 removeCandidate.ForEach（Page.Header.Controls.Remove）； } } 受保护的覆盖无效AddParsedSubObject（对象obj）
问题很简单。当使用ASP.NET主题时，您对如何将样式表呈现到页面上没有多少发言权 渲染引擎使用链接.Href.StartsWith（themePath））.ToList（）按字母顺序添加主题文件夹中的所有样式表； //删除自动添加的样式表 removeCandidate.ForEach（Page.Header.Controls.Remove）； } } 受保护的覆盖无效AddParsedSubObject（对象obj） { //仅添加样式控件 如果（obj是样式） base.AddParsedSubObject（obj）； } } } 以及样式控件的代码：
using System.ComponentModel;
using System.Security.Permissions;
using System.Web;
using System.Web.UI;
[assembly: TagPrefix("Assimilated.Extensions.Web.Controls", "ass")]
namespace Assimilated.WebControls.Stylesheet
{
[AspNetHostingPermission(SecurityAction.Demand, Level = AspNetHostingPermissionLevel.Minimal)]
[AspNetHostingPermission(SecurityAction.InheritanceDemand, Level = AspNetHostingPermissionLevel.Minimal)]
[DefaultProperty("CssUrl")]
[ParseChildren(true, "InlineStyle")]
[PersistChildren(false)]
[ToolboxData("<{0}:Style runat=\"server\"></{0}:Style>")]
[Themeable(true)]
public class Style : Control
{
public Style()
{
// set default value... for some reason the DefaultValue attribute do
// not set this as I would have expected.
TargetMedia = "All";
}
#region Properties
[Browsable(true)]
[Category("Style sheet")]
[DefaultValue("")]
[Description("The url to the style sheet.")]
[UrlProperty("*.css")]
public string CssUrl
{
get; set;
}
[Browsable(true)]
[Category("Style sheet")]
[DefaultValue("All")]
[Description("The target media(s) of the style sheet. See http://www.w3.org/TR/REC-CSS2/media.html for more information.")]
public string TargetMedia
{
get; set;
}
[Browsable(true)]
[Category("Style sheet")]
[DefaultValue(EmbedType.Link)]
[Description("Specify how to embed the style sheet on the page.")]
public EmbedType Type
{
get; set;
}
[Browsable(false)]
[PersistenceMode(PersistenceMode.InnerDefaultProperty)]
public string InlineStyle
{
get; set;
}
[Browsable(true)]
[Category("Conditional comment")]
[DefaultValue("")]
[Description("Specifies a conditional comment expression to wrap the style sheet in. See http://msdn.microsoft.com/en-us/library/ms537512.aspx")]
public string ConditionalCommentExpression
{
get; set;
}
[Browsable(true)]
[Category("Conditional comment")]
[DefaultValue(CommentType.DownlevelHidden)]
[Description("Whether to reveal the conditional comment expression to downlevel browsers. Default is to hide. See http://msdn.microsoft.com/en-us/library/ms537512.aspx")]
public CommentType ConditionalCommentType
{
get; set;
}
[Browsable(true)]
[Category("Behavior")]
public override string SkinID { get; set; }
#endregion
protected override void Render(HtmlTextWriter writer)
{
// add empty line to make output pretty
writer.WriteLine();
// prints out begin condition comment tag
if (!string.IsNullOrEmpty(ConditionalCommentExpression))
writer.WriteLine(ConditionalCommentType == CommentType.DownlevelRevealed ? "<!{0}>" : "<!--{0}>",
ConditionalCommentExpression);
if (!string.IsNullOrEmpty(CssUrl))
{
// add shared attribute
writer.AddAttribute(HtmlTextWriterAttribute.Type, "text/css");
// render either import or link tag
if (Type == EmbedType.Link)
{
// <link href=\"{0}\" type=\"text/css\" rel=\"stylesheet\" media=\"{1}\" />
writer.AddAttribute(HtmlTextWriterAttribute.Href, ResolveUrl(CssUrl));
writer.AddAttribute(HtmlTextWriterAttribute.Rel, "stylesheet");
writer.AddAttribute("media", TargetMedia);
writer.RenderBeginTag(HtmlTextWriterTag.Link);
writer.RenderEndTag();
}
else
{
// <style type="text/css">@import "modern.css" screen;</style>
writer.RenderBeginTag(HtmlTextWriterTag.Style);
writer.Write("@import \"{0}\" {1};", ResolveUrl(CssUrl), TargetMedia);
writer.RenderEndTag();
}
}
if(!string.IsNullOrEmpty(InlineStyle))
{
// <style type="text/css">... inline style ... </style>
writer.AddAttribute(HtmlTextWriterAttribute.Type, "text/css");
writer.RenderBeginTag(HtmlTextWriterTag.Style);
writer.Write(InlineStyle);
writer.RenderEndTag();
}
// prints out end condition comment tag
if (!string.IsNullOrEmpty(ConditionalCommentExpression))
{
// add empty line to make output pretty
writer.WriteLine();
writer.WriteLine(ConditionalCommentType == CommentType.DownlevelRevealed ? "<![endif]>" : "<![endif]-->");
}
}
}
public enum EmbedType
{
Link = 0,
Import = 1,
}
public enum CommentType
{
DownlevelHidden = 0,
DownlevelRevealed = 1
}
}
使用System.ComponentModel；
使用System.Security.Permissions；
使用System.Web；
使用System.Web.UI；
[汇编:TagPrefix（“assiminated.Extensions.Web.Controls”、“ass”）]
命名空间已同化.WebControls.Stylesheet
{
[AspNetHostingPermission（SecurityAction.Demand，Level=AspNetHostingPermissionLevel.Minimal）]
[AspNetHostingPermission（SecurityAction.InheritanceDemand，Level=AspNetHostingPermissionLevel.Minimal）]
[违约财产（“CssUrl”）]
[ParseChildren（true，“InlineStyle”）]
[儿童(假)]
[ToolboxData（“”）
[主题（正确）]
公共类样式：控件
{
公共风格（）
{
//设置默认值…由于某些原因，DefaultValue属性
//没有像我预期的那样设置这个。
TargetMedia=“全部”；
}
#区域属性
[可浏览（正确）]
[类别（“样式表”）]
[默认值（“”）
[说明（“样式表的url”）]
[UrlProperty（“*.css”）]
公共字符串CssUrl
{
获得；设置；
}
[可浏览（正确）]
[类别（“样式表”）]
[默认值（“全部”）]
[说明（“样式表的目标媒体。请参阅http://www.w3.org/TR/REC-CSS2/media.html 有关详细信息，请参阅。“）]
公共字符串TargetMedia
{
获得；设置；
}
[可浏览（正确）]
[类别（“样式表”）]
[默认值（EmbedType.Link）]
[说明（“指定如何在页面上嵌入样式表。”）]
公共嵌入类型
{
获得；设置；
}
[可浏览（错误）]
[PersistenceMode（PersistenceMode.InnerDefaultProperty）]
公共字符串内联样式
{
获得；设置；
}
[可浏览（正确）]
[类别（“有条件评论”）]
[默认值（“”）
[说明”（“指定用于包装样式表的条件注释表达式。请参阅http://msdn.microsoft.com/en-us/library/ms537512.aspx")]
公共字符串条件注释表达式
{
获得；设置；
}
[可浏览（正确）]
[类别（“有条件评论”）]
[默认值（CommentType.DownlevelHidden）]
[说明（“是否向下级浏览器显示条件注释表达式。默认设置为隐藏。请参阅http://msdn.microsoft.com/en-us/library/ms537512.aspx")]
公共评论类型条件评论类型
{
获得；设置；
}
[可浏览（正确）]
[类别（“行为”）]
公共重写字符串SkinID{get；set；}
#端区
受保护的覆盖无效渲染（HtmlTextWriter编写器）
{
//添加空行以使输出美观
writer.WriteLine（）；
//打印开始条件注释标记
如果（！string.IsNullOrEmpty（ConditionalCommentExpression））
writer.WriteLine（ConditionalCommentType==CommentType.DownlevelDisplayed？”：“”）；
}
}
}
公共枚举嵌入类型
{
Link=0，
导入=1，
}
公共枚举类型
{
DownlevelHidden=0，
向下水平=1
}
}
致以最良好的祝愿，艾吉尔。找到了我自己问题的答案 在设计模式下出现渲染错误的原因是VisualStudioSP1中的一个明显错误 因此，上述代码也可以在设计模式下正常工作，只要您只是在预编译的程序集中包含自定义控件，而不是通过同一解决方案中的另一个项目 请参阅上面的链接，了解如何以及为什么这样做的更详细说明 工作非常顺利
对于那些像我这样永远记不起Re:使用特定媒体CSS文件语法的人，你可以使用@media CSS语句，效果很好。感谢Simon的好话。这确实是我的第一个自定义控件，但现在已经重构了几次，所以是第一个自定义控件，而不是第一次尝试：）@egil有趣的是，我第二天就切换到了MVC——部分原因是我厌倦了像你这样寻找解决简单问题的聪明解决方案。幸运的是，我正在开发一个新网站，所以我被允许享受MVC带来的奢华，我真的很享受
<ass:StylePlaceHolder1runat="server" SkinId="ThemeStyles">
<ass:Style CssUrl="~/App_Themes/Default/01reset.css" />
<ass:Style CssUrl="~/App_Themes/Default/02style.css" />
<ass:Style CssUrl="~/App_Themes/Default/99iefix.css" ConditionCommentExpression="[if IE]" />
</ass:StylePlaceHolder1>
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Linq;
using System.Security.Permissions;
using System.Web;
using System.Web.UI;
using System.Web.UI.HtmlControls;
[assembly: TagPrefix("Assimilated.Extensions.Web.Controls", "ass")]
namespace Assimilated.WebControls.Stylesheet
{
[AspNetHostingPermission(SecurityAction.Demand, Level = AspNetHostingPermissionLevel.Minimal)]
[AspNetHostingPermission(SecurityAction.InheritanceDemand, Level = AspNetHostingPermissionLevel.Minimal)]
[DefaultProperty("SkinID")]
[ToolboxData("<{0}:StylePlaceHolder runat=\"server\" SkinID=\"ThemeStyles\"></{0}:StylePlaceHolder>")]
[ParseChildren(true, "Styles")]
[Themeable(true)]
[PersistChildren(false)]
public class StylePlaceHolder : Control
{
private List<Style> _styles;
[Browsable(true)]
[Category("Behavior")]
[DefaultValue("ThemeStyles")]
public override string SkinID { get; set; }
[Browsable(false)]
public List<Style> Styles
{
get
{
if (_styles == null)
_styles = new List<Style>();
return _styles;
}
}
protected override void CreateChildControls()
{
if (_styles == null)
return;
// add child controls
Styles.ForEach(Controls.Add);
}
protected override void OnLoad(EventArgs e)
{
base.OnLoad(e);
// get notified when page has finished its load stage
Page.LoadComplete += Page_LoadComplete;
}
void Page_LoadComplete(object sender, EventArgs e)
{
// only remove if the page is actually using themes
if (!string.IsNullOrEmpty(Page.StyleSheetTheme) || !string.IsNullOrEmpty(Page.Theme))
{
// Make sure only to remove style sheets from the added by
// the runtime form the current theme.
var themePath = string.Format("~/App_Themes/{0}",
!string.IsNullOrEmpty(Page.StyleSheetTheme)
? Page.StyleSheetTheme
: Page.Theme);
// find all existing stylesheets in header
var removeCandidate = Page.Header.Controls.OfType<HtmlLink>()
.Where(link => link.Href.StartsWith(themePath)).ToList();
// remove the automatically added style sheets
removeCandidate.ForEach(Page.Header.Controls.Remove);
}
}
protected override void AddParsedSubObject(object obj)
{
// only add Style controls
if (obj is Style)
base.AddParsedSubObject(obj);
}
}
}
using System.ComponentModel;
using System.Security.Permissions;
using System.Web;
using System.Web.UI;
[assembly: TagPrefix("Assimilated.Extensions.Web.Controls", "ass")]
namespace Assimilated.WebControls.Stylesheet
{
[AspNetHostingPermission(SecurityAction.Demand, Level = AspNetHostingPermissionLevel.Minimal)]
[AspNetHostingPermission(SecurityAction.InheritanceDemand, Level = AspNetHostingPermissionLevel.Minimal)]
[DefaultProperty("CssUrl")]
[ParseChildren(true, "InlineStyle")]
[PersistChildren(false)]
[ToolboxData("<{0}:Style runat=\"server\"></{0}:Style>")]
[Themeable(true)]
public class Style : Control
{
public Style()
{
// set default value... for some reason the DefaultValue attribute do
// not set this as I would have expected.
TargetMedia = "All";
}
#region Properties
[Browsable(true)]
[Category("Style sheet")]
[DefaultValue("")]
[Description("The url to the style sheet.")]
[UrlProperty("*.css")]
public string CssUrl
{
get; set;
}
[Browsable(true)]
[Category("Style sheet")]
[DefaultValue("All")]
[Description("The target media(s) of the style sheet. See http://www.w3.org/TR/REC-CSS2/media.html for more information.")]
public string TargetMedia
{
get; set;
}
[Browsable(true)]
[Category("Style sheet")]
[DefaultValue(EmbedType.Link)]
[Description("Specify how to embed the style sheet on the page.")]
public EmbedType Type
{
get; set;
}
[Browsable(false)]
[PersistenceMode(PersistenceMode.InnerDefaultProperty)]
public string InlineStyle
{
get; set;
}
[Browsable(true)]
[Category("Conditional comment")]
[DefaultValue("")]
[Description("Specifies a conditional comment expression to wrap the style sheet in. See http://msdn.microsoft.com/en-us/library/ms537512.aspx")]
public string ConditionalCommentExpression
{
get; set;
}
[Browsable(true)]
[Category("Conditional comment")]
[DefaultValue(CommentType.DownlevelHidden)]
[Description("Whether to reveal the conditional comment expression to downlevel browsers. Default is to hide. See http://msdn.microsoft.com/en-us/library/ms537512.aspx")]
public CommentType ConditionalCommentType
{
get; set;
}
[Browsable(true)]
[Category("Behavior")]
public override string SkinID { get; set; }
#endregion
protected override void Render(HtmlTextWriter writer)
{
// add empty line to make output pretty
writer.WriteLine();
// prints out begin condition comment tag
if (!string.IsNullOrEmpty(ConditionalCommentExpression))
writer.WriteLine(ConditionalCommentType == CommentType.DownlevelRevealed ? "<!{0}>" : "<!--{0}>",
ConditionalCommentExpression);
if (!string.IsNullOrEmpty(CssUrl))
{
// add shared attribute
writer.AddAttribute(HtmlTextWriterAttribute.Type, "text/css");
// render either import or link tag
if (Type == EmbedType.Link)
{
// <link href=\"{0}\" type=\"text/css\" rel=\"stylesheet\" media=\"{1}\" />
writer.AddAttribute(HtmlTextWriterAttribute.Href, ResolveUrl(CssUrl));
writer.AddAttribute(HtmlTextWriterAttribute.Rel, "stylesheet");
writer.AddAttribute("media", TargetMedia);
writer.RenderBeginTag(HtmlTextWriterTag.Link);
writer.RenderEndTag();
}
else
{
// <style type="text/css">@import "modern.css" screen;</style>
writer.RenderBeginTag(HtmlTextWriterTag.Style);
writer.Write("@import \"{0}\" {1};", ResolveUrl(CssUrl), TargetMedia);
writer.RenderEndTag();
}
}
if(!string.IsNullOrEmpty(InlineStyle))
{
// <style type="text/css">... inline style ... </style>
writer.AddAttribute(HtmlTextWriterAttribute.Type, "text/css");
writer.RenderBeginTag(HtmlTextWriterTag.Style);
writer.Write(InlineStyle);
writer.RenderEndTag();
}
// prints out end condition comment tag
if (!string.IsNullOrEmpty(ConditionalCommentExpression))
{
// add empty line to make output pretty
writer.WriteLine();
writer.WriteLine(ConditionalCommentType == CommentType.DownlevelRevealed ? "<![endif]>" : "<![endif]-->");
}
}
}
public enum EmbedType
{
Link = 0,
Import = 1,
}
public enum CommentType
{
DownlevelHidden = 0,
DownlevelRevealed = 1
}
}
<%@ Register TagPrefix="ass" Namespace="Assimilated.WebControls.Stylesheet" %>