CssStyleCollection.cs :  » 2.6.4-mono-.net-core » System.Web » System » Web » UI » C# / CSharp Open Source

//
// System.Web.UI.CssStyleCollection.cs
//
// Authors:
//   Duncan Mak  (duncan@ximian.com)
//   Gonzalo Paniagua (gonzalo@ximian.com)
//
// (C) 2002 Ximian, Inc. (http://www.ximian.com)
// Copyright (C) 2005-2010 Novell, Inc (http://www.novell.com)
//
// Permission is hereby granted, free of charge, to any person obtaining
// a copy of this software and associated documentation files (the
// "Software"), to deal in the Software without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Software, and to
// permit persons to whom the Software is furnished to do so, subject to
// the following conditions:
// 
// The above copyright notice and this permission notice shall be
// included in all copies or substantial portions of the Software.
// 
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
//

using System.IO;
using System.Collections;
using System.Security.Permissions;
using System.Text;
using System.Collections.Specialized;
using System.Globalization;
using System.Web.Util;

namespace System.Web.UI{

  // CAS - no InheritanceDemand here as the class is sealed
  [AspNetHostingPermission (SecurityAction.LinkDemand, Level = AspNetHostingPermissionLevel.Minimal)]
  public sealed class CssStyleCollection
  {
    StateBag bag;
    ListDictionary style;
    StringBuilder _value = new StringBuilder ();
    
    internal CssStyleCollection ()
    {
      style = new ListDictionary (StringComparer.OrdinalIgnoreCase);
    }

    internal CssStyleCollection (StateBag bag) : this ()
    {
      this.bag = bag;
      if (bag != null && bag [AttributeCollection.StyleAttribute] != null)
        _value.Append (bag [AttributeCollection.StyleAttribute]);
      InitFromStyle ();
    }

    void InitFromStyle ()
    {
      style.Clear ();
      if (_value.Length > 0) {
        int startIndex = 0;
        while (startIndex >= 0)
          startIndex = ParseStyle (startIndex);
      }
    }

    int ParseStyle (int startIndex)
    {
      int colon = -1;
      for (int i = startIndex; i < _value.Length; i++) {
        if (_value [i] == ':') {
          colon = i;
          break;
        }
      }
      if (colon == -1 || colon + 1 == _value.Length)
        return -1;

      string key = _value.ToString (startIndex, colon - startIndex).Trim ();

      int semicolon = -1;
      for (int i = colon + 1; i < _value.Length; i++) {
        if (_value [i] == ';') {
          semicolon = i;
          break;
        }
      }
      string value;
      if (semicolon == -1)
        value = _value.ToString (colon + 1, _value.Length - colon - 1).Trim ();
      else
        value = _value.ToString (colon + 1, semicolon - colon - 1).Trim ();

      style.Add (key, value);
      if (semicolon == -1 || semicolon + 1 == _value.Length)
        return -1;

      return semicolon + 1;
    }

    void BagToValue ()
    {
      _value.Length = 0;
      foreach (string key in style.Keys)
        AppendStyle (_value, key, (string) style [key]);
    }

    static void AppendStyle (StringBuilder sb, string key, string value)
    {
      if (String.Compare (key, "background-image", StringComparison.OrdinalIgnoreCase) == 0 &&
          value.Length >= 3 && String.Compare ("url", 0, value, 0, 3, StringComparison.OrdinalIgnoreCase) != 0)
        sb.AppendFormat ("{0}:url({1});", key, HttpUtility.UrlPathEncode (value));
      else
        sb.AppendFormat ("{0}:{1};", key, value);
    }

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

    public string this [string key] {
      get { return style [key] as string; }
      set { Add (key, value); }
    }

    public ICollection Keys {
      get { return style.Keys; }
    }

    public void Add (string key, string value)
    {
      if (key == null)
        throw new ArgumentNullException ("key");

      if (value == null) {
        Remove (key);
        return;
      }

      string curr = (string) style [key];
      if (curr == null) {
        // just append
        style [key] = value;
        AppendStyle (_value, key, value);
      } else if (String.CompareOrdinal (curr, value) == 0) {
        // do nothing
        return;
      } else {
        style [key] = value;
        BagToValue ();
      }

      if (bag != null)
        bag [AttributeCollection.StyleAttribute] = _value.ToString ();
    }

    public void Add (HtmlTextWriterStyle key, string value)
    {
      Add (HtmlTextWriter.StaticGetStyleName (key), value);
    }

    public void Clear ()
    {
      style.Clear ();
      SetValueInternal (null);
    }

    public void Remove (string key)
    {
      if (style [key] == null)
        return;
      style.Remove (key);
      if (style.Count == 0)
        SetValueInternal (null);
      else
        BagToValue ();
    }

    public string this [HtmlTextWriterStyle key] {
      get { return style [HtmlTextWriter.StaticGetStyleName (key)] as string; }
      set { Add (HtmlTextWriter.StaticGetStyleName (key), value); }
    }

    public void Remove (HtmlTextWriterStyle key)
    {
      Remove (HtmlTextWriter.StaticGetStyleName (key));
    }

    public string Value {
      get { return _value.ToString (); }
      set {
        SetValueInternal (value);
        InitFromStyle ();
      }
    }

    void SetValueInternal (string value)
    {
      _value.Length = 0;
      if (value != null)
        _value.Append (value);
      if (bag != null) {
        if (value == null)
          bag.Remove (AttributeCollection.StyleAttribute);
        else
          bag [AttributeCollection.StyleAttribute] = value;
      }
    }
  }
}