我目前有一个使用 KeyValuePair
和 List
存储以键值对格式为 Key = track,Value = artist 的音轨集合的类。
我想提供一种查找特定音轨并返回整个匹配 CD 的方法。
这是我目前的尝试:
public CompilationCD FindTrackInComCD(string track)
{
CompilationCD temp = new CompilationCD();
List<CD> tempComCols = _cdCollection.FindAll(delegate(CD cd)
{ return cd.GetType() == temp.GetType(); });
foreach (KeyValuePair<string, string> comCD in tempComCols)
{
if (comCD.Key.Contains(track))
{
return comCD;
}
}
throw new ArgumentException("No matches found");
}
我有一个 CD 类型的 CD 集合(List<CD>
),因此我通过将其与临时列表进行比较来创建一个适当类型的新的 List<>
。
编译时我会得到以下错误:
Cannot convert type 'CDCollection.CD' to System.Collections.Generic.KeyValuePair<string,string>'
Cannot implicitly convert type 'System.Collections.Generic.KeyValuePair<string,string>'
是我的项目命名空间,和是类。
抱歉,这似乎是我之前问过的一个类似的问题。我尝试使用我之前得到的方法,但我有点困惑;我很少使用 >或。这是类:
using System;
使用System.Collections; 使用System.Collections.Generic; 使用System.Linq; 使用System.Text;
命名空间CDCollection { public class CD { #region 字段 private readonly string _artist; private readonly string _album; private List _track = new List(); #endregion } }
#region Constructors
public CD()
{
_artist = "";
_album = "";
_track = null;
}
public CD(string albumName)
{
_album = albumName;
}
public CD(string artistName, string albumName)
{
_artist = artistName;
_album = albumName;
}
#endregion
#region Properties
/// <summary>
/// Get/Set Artist Name
/// </summary>
public virtual string Artist
{
get
{
return _artist;
}
set
{
value = _artist;
}
}
/// <summary>
/// Get/Set Album
/// </summary>
public string Album
{
get
{
return _album;
}
set
{
value = _album;
}
}
/// <summary>
/// Get/Set Track Name
/// </summary>
public virtual List<string> Track
{
get
{
return _track;
}
set
{
value = _track;
}
}
#endregion
#region ToString()
/// <summary>
/// Custom ToString() Method
/// </summary>
/// <returns></returns>
public override string ToString()
{
//Create new StringBuilder object
StringBuilder sb = new StringBuilder();
sb.Append("Artist Name");
//Display error if Artist is not available
if (_artist == null || _artist == "")
{
sb.Append("\nNo Artist Entered");
}
else
{
sb.Append("\n" + this._artist);
}
sb.Append("\n");
sb.Append("\nAlbum Name");
//Display error if Album is not available
if (_album == null || _album == "")
{
sb.Append("\nNo Album Entered");
}
else
{
sb.Append("\n" + this._album);
}
sb.Append("\n");
sb.Append("\nTrack Name");
sb.Append("\n");
//Iterate through all tracks stored in list
foreach (string trackName in _track)
{
//Print each artist
sb.Append("\n" + trackName);
}
sb.Append("\nEnd of CD Record.........");
return sb.ToString();
}
#endregion
}
这是 CompilationCD 类:
using System;
使用 System.Collections.Generic; 使用 System.Linq; 使用 System.Text;
命名空间 CDCollection { public class CompilationCD : CD { #region 字段
private readonly string _artist;
private readonly string _album;
private List<KeyValuePair<string,string>> _tracks = new List<KeyValuePair<string,string>>();
//List<KeyValuePair> Reference.
//http://msdn.microsoft.com/en-us/library/6sh2ey19(VS.85).aspx
#endregion
#region Constructors
public CompilationCD()
{
_album = "";
_artist = "Various Artists";
}
public CompilationCD(string albumName):base(albumName)
{
_album = albumName;
_artist = "Various Artists";
}
#endregion
public void AddTracks(string track, string artist)
{
_tracks.Add(new KeyValuePair<string, string>(track, artist));
}
#region Properties
public override string Artist
{
get
{
return this._artist;
}
}
public new List<KeyValuePair<string,string>> Track
{
get
{
return _tracks;
}
set
{
_tracks = value;
}
}
#endregion
#region ToString()
//TEST
public override string ToString()
{
//Create new StringBuilder object
StringBuilder sb = new StringBuilder();
sb.Append("Artist Name");
//Display error if Artist is not available
if (_artist == null || _artist == "")
{
sb.Append("\nNo Artist Entered");
}
else
{
sb.Append("\n" + this._artist);
}
sb.Append("\n");
sb.Append("\nAlbum Name");
//Display error if Album is not available
if (base.Album == null || base.Album == "")
{
sb.Append("\nNo Album Entered");
}
else
{
sb.Append("\n" + base.Album);
}
sb.Append("\n");
sb.Append("\nTrack Name");
sb.Append("\n");
////Iterate through all tracks stored in list
//foreach (string trackName in base.Track)
//{
// //Print each artist
// sb.Append("\n" + trackName);
//}
for(int i = 0; i <= _tracks.Count; i++)
{
string track = _tracks[i].Key;
string artist = _tracks[i].Value;
sb.Append("\nTrack");
sb.Append(track);
sb.Append("\nArtist");
sb.Append(artist);
}
sb.Append("\nEnd of Compilation CD Record.........");
return sb.ToString();
}
#endregion
}
我有严格的规则,必须从CD继承来创建我的CompilationCD,同时使用List>来存储我的曲目集合,它需要保存曲目和艺术家。很疯狂,我知道 =/
此外,我必须将所有类型的cd存储在类型为CD的列表中(List)。
is
而不是比较GetType()
的返回值。这样做更快、更简短,而且与可扩展性更好(例如,如果以后从CompilationCD
派生某个类)。 - Pavel Minaev