Linq Any返回true，儘管集合中的所有值都是假的

我在屬性值計算中看到了非常奇怪的行爲。我有一個屬性HasChanged，如果它的任何依賴屬性爲true，則爲true。但是我得到了一個結果 - 所有參數都是錯誤的，結果是真的。我使用MVVM燈框架，每個屬性INotifyPropertyChanged的Linq Any返回true，儘管集合中的所有值都是假的

下面是輔助功能

private static bool PropertyWrapper(bool value, [CallerMemberName] string callerName = "") 
    { 
     Logger.Debug($"[{callerName}: {value}]"); 
     return value; 
    } 

    private static T PropertyWrapper<T>(Expression<Func<T>> property) 
    { 
     var compiled = property.Compile(); 
     var result = (T)compiled.DynamicInvoke(); 
     Logger.Debug($"[{GetName(property)}: {result}]"); 
     return result; 
    } 

    private static string GetName<T>(Expression<Func<T>> expr) 
    { 
     var mexpr = expr.Body as MemberExpression; 
     if (mexpr == null) return "(null)"; 
     if (mexpr.Member == null) return "((null))"; 
     return mexpr.Member.Name; 
    }

這是代碼

public virtual bool HasChanged => PropertyWrapper(new[] { 
     PropertyWrapper(() => TitleChanged), 
     PropertyWrapper(() => EnglishTitleChanged), 
     PropertyWrapper(() => OriginalTitleChanged), 
     PropertyWrapper(() => PlotChanged), 
     PropertyWrapper(() => OutlineChanged), 
     PropertyWrapper(() => DirectorChanged), 
     PropertyWrapper(() => YearChanged), 
     PropertyWrapper(() => MovieRolesChanged), 
     PropertyWrapper(() => GenresChanged), 
     PropertyWrapper(() => CountriesChanged) 
    }.Any(), "HasChanged"); 

    public bool YearChanged => this.state == State.Edit && this.source.MovieDescription.Year != this.clone.MovieDescription.Year; 
    public bool TitleChanged => HasTitleChanges(); 
    public bool EnglishTitleChanged => HasEnglishTitleChanges(); 
    public bool OriginalTitleChanged => HasOriginalTitleChanges(); 
    public bool PlotChanged => HasDescriptionChanges(); 
    public bool DirectorChanged => HasDirectorChanges(); 
    public bool OutlineChanged => HasOutlineChanges(); 
    public bool MovieRolesChanged => HasMovieRolesChanges(); 
    public bool CountriesChanged => HasCountriesChanges(); 
    public bool GenresChanged => HasGenresChanges();

，什麼是寫入日誌

[TitleChanged：False]

[EnglishTitleChanged：FALSE]

[OriginalTitleChanged：FALSE]

[PlotChanged：FALSE]

[OutlineChanged：FALSE]

[DirectorChanged：FALSE]

[YearChanged ：False]

[MovieRolesChanged：False]

[GenresChanged：假]

[CountriesChanged：假]

[HasChanged：真]

它看起來不可能的枯燥，但我無法想象它怎麼可以。請給我解釋這種行爲的原因。

來源

2017-02-16 Anton

Any如果集合中有任何元素，則不返回參數返回。爲了得到你想要的，你必須檢查你的元素的值作爲Any斷言：

public virtual bool HasChanged => PropertyWrapper(new[] { 
     //... 
     }.Any(q => q), "HasChanged");

來源

2017-02-16 07:25:25 slawekwin

總體正確，但元素是布爾，不是代表，所以它應該是'。任何（Q => Q） ' –

@IvanStoev，謝謝，編輯。我很困惑那裏有很多lambdas :) – slawekwin

Linq Any返回true，儘管集合中的所有值都是假的

回答

相關問題