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// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
// See the LICENSE file in the project root for more information.
//
//
// Description:
// ContentLocatorPart represents a set of name/value pairs that identify a
// piece of data within a certain context. The names and values are
// strings.
//
// Spec: Simplifying Store Cache Model.doc
//
using System;
using System.Collections;
using System.Collections.Generic;
using System.ComponentModel;
using System.Diagnostics;
namespace MS.Internal.Annotations
{
/// <summary>
/// ContentLocatorPart represents a set of name/value pairs that identify a
/// piece of data within a certain context. The names and values are
/// all strings.
/// </summary>
internal class ObservableDictionary : IDictionary<string, string>, INotifyPropertyChanged
{
//------------------------------------------------------
//
// Constructors
//
//------------------------------------------------------
#region Constructors
/// <summary>
/// Creates a ContentLocatorPart with the specified type name and namespace.
/// </summary>
public ObservableDictionary()
{
_nameValues = new Dictionary<string, string>();
}
#endregion Constructors
//------------------------------------------------------
//
// Public Methods
//
//------------------------------------------------------
#region Public Methods
/// <summary>
/// Adds a key/value pair to the ContentLocatorPart. If a value for the key already
/// exists, the old value is overwritten by the new value.
/// </summary>
/// <param name="key">key</param>
/// <param name="val">value</param>
/// <exception cref="ArgumentNullException">key or val is null</exception>
/// <exception cref="ArgumentException">a value for key is already present in the locator part</exception>
public void Add(string key, string val)
{
ArgumentNullException.ThrowIfNull(key);
ArgumentNullException.ThrowIfNull(val);
_nameValues.Add(key, val);
FireDictionaryChanged();
}
/// <summary>
/// Removes all name/value pairs from the ContentLocatorPart.
/// </summary>
public void Clear()
{
int count = _nameValues.Count;
if (count > 0)
{
_nameValues.Clear();
// Only fire changed event if the dictionary actually changed
FireDictionaryChanged();
}
}
/// <summary>
/// Returns whether or not a value of the key exists in this ContentLocatorPart.
/// </summary>
/// <param name="key">the key to check for</param>
/// <returns>true - yes, false - no</returns>
public bool ContainsKey(string key)
{
return _nameValues.ContainsKey(key);
}
/// <summary>
/// Removes the key and its value from the ContentLocatorPart.
/// </summary>
/// <param name="key">key to be removed</param>
/// <returns>true - the key was found in the ContentLocatorPart, false o- it wasn't</returns>
public bool Remove(string key)
{
bool exists = _nameValues.Remove(key);
// Only fire changed event if the key was actually removed
if (exists)
{
FireDictionaryChanged();
}
return exists;
}
/// <summary>
/// Returns an enumerator for the key/value pairs in this ContentLocatorPart.
/// </summary>
/// <returns>an enumerator for the key/value pairs; never returns null</returns>
IEnumerator IEnumerable.GetEnumerator()
{
return _nameValues.GetEnumerator();
}
/// <summary>
/// Returns an enumerator for the key/value pairs in this ContentLocatorPart.
/// </summary>
/// <returns>an enumerator for the key/value pairs; never returns null</returns>
public IEnumerator<KeyValuePair<string, string>> GetEnumerator()
{
return ((IEnumerable<KeyValuePair<string, string>>)_nameValues).GetEnumerator();
}
/// <summary>
///
/// </summary>
/// <param name="key"></param>
/// <param name="value"></param>
/// <returns></returns>
/// <exception cref="ArgumentNullException">key is null</exception>
public bool TryGetValue(string key, out string value)
{
ArgumentNullException.ThrowIfNull(key);
return _nameValues.TryGetValue(key, out value);
}
/// <summary>
///
/// </summary>
/// <param name="pair"></param>
/// <exception cref="ArgumentNullException">pair is null</exception>
void ICollection<KeyValuePair<string, string>>.Add(KeyValuePair<string, string> pair)
{
((ICollection<KeyValuePair<string, string>>)_nameValues).Add(pair);
}
/// <summary>
///
/// </summary>
/// <param name="pair"></param>
/// <returns></returns>
/// <exception cref="ArgumentNullException">pair is null</exception>
bool ICollection<KeyValuePair<string, string>>.Contains(KeyValuePair<string, string> pair)
{
return ((ICollection<KeyValuePair<string, string>>)_nameValues).Contains(pair);
}
/// <summary>
///
/// </summary>
/// <param name="pair"></param>
/// <returns></returns>
/// <exception cref="ArgumentNullException">pair is null</exception>
bool ICollection<KeyValuePair<string, string>>.Remove(KeyValuePair<string, string> pair)
{
return ((ICollection<KeyValuePair<string, string>>)_nameValues).Remove(pair);
}
/// <summary>
///
/// </summary>
/// <param name="target"></param>
/// <param name="startIndex"></param>
/// <exception cref="ArgumentNullException">target is null</exception>
/// <exception cref="ArgumentOutOfRangeException">startIndex is less than zero or greater than the lenght of target</exception>
void ICollection<KeyValuePair<string, string>>.CopyTo(KeyValuePair<string, string>[] target, int startIndex)
{
ArgumentNullException.ThrowIfNull(target);
ArgumentOutOfRangeException.ThrowIfNegative(startIndex);
ArgumentOutOfRangeException.ThrowIfGreaterThan(startIndex, target.Length);
((ICollection<KeyValuePair<string, string>>)_nameValues).CopyTo(target, startIndex);
}
#endregion Public Methods
//------------------------------------------------------
//
// Public Operators
//
//------------------------------------------------------
//------------------------------------------------------
//
// Public Events
//
//------------------------------------------------------
//------------------------------------------------------
//
// Public Properties
//
//------------------------------------------------------
#region Public Properties
/// <summary>
/// The number of name/value pairs in this ContentLocatorPart.
/// </summary>
/// <value>count of name/value pairs</value>
public int Count
{
get
{
return _nameValues.Count;
}
}
/// <summary>
/// Indexer provides lookup of values by key. Gets or sets the value
/// in the ContentLocatorPart for the specified key. If the key does not exist
/// in the ContentLocatorPart,
/// </summary>
/// <param name="key">key</param>
/// <returns>the value stored in this locator part for key</returns>
public string this[string key]
{
get
{
ArgumentNullException.ThrowIfNull(key);
string value = null;
_nameValues.TryGetValue(key, out value);
return value;
}
set
{
ArgumentNullException.ThrowIfNull(key);
ArgumentNullException.ThrowIfNull(value);
string oldValue = null;
_nameValues.TryGetValue(key, out oldValue);
// If the new value is actually different, then we add it and fire
// a change notification
if ((oldValue == null) || (oldValue != value))
{
_nameValues[key] = value;
FireDictionaryChanged();
}
}
}
/// <summary>
///
/// </summary>
public bool IsReadOnly
{
get
{
return false;
}
}
/// <summary>
/// Returns a collection of all the keys in this ContentLocatorPart.
/// </summary>
/// <value>keys</value>
public ICollection<string> Keys
{
get
{
return _nameValues.Keys;
}
}
/// <summary>
/// Returns a collection of all the values in this ContentLocatorPart.
/// </summary>
/// <value>values</value>
public ICollection<string> Values
{
get
{
return _nameValues.Values;
}
}
#endregion Public Properties
//------------------------------------------------------
//
// Public Events
//
//------------------------------------------------------
//------------------------------------------------------
//
// Internal Methods
//
//------------------------------------------------------
//------------------------------------------------------
//
// Internal Operators
//
//------------------------------------------------------
//------------------------------------------------------
//
// Internal Events
//
//------------------------------------------------------
#region Public Events
/// <summary>
///
/// </summary>
public event PropertyChangedEventHandler PropertyChanged;
#endregion Public Events
//------------------------------------------------------
//
// Internal Properties
//
//------------------------------------------------------
//------------------------------------------------------
//
// Private Methods
//
//------------------------------------------------------
#region Private Methods
/// <summary>
/// Notify the owner this ContentLocatorPart has changed.
/// </summary>
private void FireDictionaryChanged()
{
if (PropertyChanged != null)
{
PropertyChanged(this, new PropertyChangedEventArgs(null));
}
}
#endregion Private Methods
//------------------------------------------------------
//
// Private Fields
//
//------------------------------------------------------
#region Private Fields
/// <summary>
/// The internal data structure.
/// </summary>
private Dictionary<string, string> _nameValues;
#endregion Private Fields
}
}
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