CODEWITHSUNDEEP
c#vb.netlinq
sovantha
sovantha

Reputation: 259

What is the C# equivalance of the Aggregate keyword in VB Linq?

I'm not a big fan of VB. Can anyone help me make this piece of code in c#?

 Public ReadOnly Property HasErrors() As Boolean
        Get
            Return (Aggregate o In Me _
                    Let errObj = TryCast(o, IDataErrorInfo) _
                    Where If(errObj IsNot Nothing, errObj.Error <> Nothing, False) _
                    Into Count()) > 0
        End Get
    End Property

Update

Public MustInherit Class MyBaseCollection(Of T)
    Inherits ObservableCollection(Of T)

    Public ReadOnly Property HasErrors() As Boolean
        Get
            Return (Aggregate o In Me _
                    Let errObj = TryCast(o, IDataErrorInfo) _
                    Where If(errObj IsNot Nothing, errObj.Error <> Nothing, False) _
                    Into Count()) > 0
        End Get
    End Property

    Sub New(ByVal query As IEnumerable(Of T), ByVal context As OMSEntities)
        MyBase.New(query)
    End Sub

End Class

Upvotes: 1

Views: 239

Answers (3)

Paulo Morgado
Paulo Morgado

Reputation: 14856

It's not the exact translation, but it'll get the same result:

public bool HasErrors
{
    get
    {
        return this.OfType<IDataErrorInfo>().Any(x => x.Error != null);
    }
}

Upvotes: 0

George Mauer
George Mauer

Reputation: 122202

I'm not 100% on what this is but I think you can do it with

this.Any(o => {
  var errObj = o as IDataErrorInfo;
  return errObj != null && errObj.Error != null
});

or you can do the more functional style:

this.Select(o => o as IDataErrorInfo)
    .Any(errObj => errObj != null && errObj.Error != null);

Upvotes: 0

MarcinJuraszek
MarcinJuraszek

Reputation: 125650

There is no equivalent for Aggregate in syntax-based query in C#. You have to use methods.

public bool HasErrors
{
    get
    {
        return this.Select(x => x as IDataErrorInfo)
                   .Where(x => x != null && x.Error != null)
                   .Count() > 0;
    }
}

Or easier version with Count(predicate) overload:

public bool HasErrors
{
    get
    {
        return this.Select(x => x as IDataErrorInfo)
                   .Count(x => x != null && x.Error != null) > 0;
    }
}

or even better with Any(predicate):

public bool HasErrors
{
    get
    {
        return this.Select(x => x as IDataErrorInfo)
                   .Any(x => x != null && x.Error != null);
    }
}

Upvotes: 1

Related Questions