Search results matching tag 'generics'

Duplicates

davidl — Mon, 14 Dec 2009 05:00:00 GMT

I have the following snippet of code:

Public MyCollection As New List(Of String)

Private Function GetFiles(ByVal strPath As String, ByVal searchList As List(Of String)) As List(Of String)
Dim matches As New List(Of String)
For Each pattern As String In searchList
matches.AddRange(System.IO.Directory.GetFiles(strPath, pattern))
Next
Return matches
End Function

Private Sub GetMyFiles(ByVal strPath As String)
Dim SupportedFormats As New List(Of String)
With SupportedFormats
.Add("*.txt")
.Add("*.doc")
End With

MyCollection.AddRange(Module1.GetFiles(strPath, SupportedFormats))

Dim DI As New System.IO.DirectoryInfo(strPath)

For Each d As System.IO.DirectoryInfo In DI.GetDirectories
Console.Writeline(d.Fullname)
Module1.GetMyFiles(d.FullName)
Next d

End Sub

Can someone please tell me why I am getting some duplicate entries and how to fix it? The Console.Writeline(d.Fullname) is showing the correct directory structure with no duplicates, but if you iterate through MyCollection there are duplicates. Please help. :)

Cheers!

problem with generics

sansat6699 — Mon, 14 Sep 2009 04:00:00 GMT

i am having

public class studentCollection:Collection <studentCollection>
    {
        //constructer
        public studentCollection(): base(new List<student>())
        {
        }

gives me error

1 Error 3 The best overloaded method match for 'System.Collections.ObjectModel.Collection<C.Bl.studentCollection>.Collection(System.Collections.Generic.IList<C.Bl.studentCollection>)' has some invalid arguments

2 Error 4 Argument '1': cannot convert from 'System.Collections.Generic.List<C.Bl.student>' to 'System.Collections.Generic.IList<C.Bl.studentCollection>'

Inheritance using generics

deswillans — Wed, 02 Sep 2009 04:00:00 GMT

I have had a good old Google to try and solve this problem and havn't managed it yet. Basically I am stuck with a compiler error saying:

Error 1 Cannot implicitly convert type 'ClassLibrary1.MeerKatCollection<ClassLibrary1.MeerKat>' to 'ClassLibrary1.MongooseCollection<ClassLibrary1.Mongoose>' ClassLibrary1 C:\My Projects\Throw aways\ClassLibrary1\Class1.cs 50 17

Below is some sample code that replicates what I am trying to achieve but can't. Please ignore the fact that the Collection classes do not implement IList or ICollection or similar. I am hoping that that is not a show stopper.

public abstract class Mongoose
	{
	}

	public class MeerKat : Mongoose
	{
	}

	public abstract class MongooseCollection<T> where T : Mongoose
	{
		private List<T> _mongeese = new List<T>();

		public abstract void Feed(T animal);

		public void LookAfter()
		{
			// some common logic to apply to all collections of mongeese
			foreach (T mongoose in _mongeese)
			{
				Feed(mongoose);
			}
		}
	}

	public class MeerKatCollection<T> : MongooseCollection<MeerKat> 
	{
		private void UpdateFedMeerkatsInDB()
		{
		}

		public override void Feed(MeerKat meerkat)
		{
			// Do the feeding
			UpdateFedMeerkatsInDB();
		}
	}

	public class Test
	{
		public Test()
		{
			MongooseCollection<Mongoose> collection;
			collection = new MeerKatCollection<MeerKat>();    // This is the line the Compiler is moaning about
 
			collection.LookAfter();	// Call method on base class that in turn uses specific knowledge of
									// domain in the instantiated derived class at runtime
		}
	}

My understandong of inheritance is that since all Meerkats are Mongeese I should be able to store a collection of them in the collection field (Defined as MongooseCollection<Mongoose>)

Any thoughts on the matter would be greatly appreciated

how to convert generic list to list of type string

cmakwana — Fri, 19 Jun 2009 04:00:00 GMT

hi,

this is sample code,

public class BackUpLogic<T>
{
public void tableBackup(List<string> columnNames, List<T> tableData) {

            foreach (string cName in columnNames)
            {

            }
           foreach (T tRow in tableData)
            {

            }
        }

    }

in second foreach ,tRow is holding data of one database table row.

i wan to convert that into string.

i dont know how to do that.

please help me.

Enumerate on Generic List, List<T>

garmang09 — Fri, 29 May 2009 04:00:00 GMT

I'm trying to use a List<T>.Enumerator on a list of custom objects and the enumerators MoveNext() returns true but Current never gets populated with any item from the list. The foreach works fine but I can't use that because I need to loop within a WF workflow so I'm forced to use a enumerator. Here is my custom object class it's pretty basic. Any suggestions would be appreciated.

1    public class Approval
2        {
3            private int _objectId;
4            private int _objectTypeId;
5    
6            public int ObjectTypeId
7            {
8                get { return _objectTypeId; }
9                set { _objectTypeId = value; }
10           }
11   
12           public int ObjectId
13           {
14               get { return _objectId; }
15               set { _objectId = value; }
16           }
17   
18           public Approval(int objectId, int objectTypeId)
19           {
20               ObjectId = objectId;
21               ObjectTypeId = objectTypeId;
22           }

Deployment project can compile when view is strongly typed to List<string>

random0xff — Wed, 18 Feb 2009 05:00:00 GMT

I need to deploy an ASP.NET MVC project, and I use the web deployment projects to do so. The app compiles and runs fine, but the deployment project has a problem with a strongly typed view in the project. it is of type System.Web.Mvc.ViewPage<List<string>> and the error message is:

Could not load type 'System.Web.Mvc.ViewPage<List<string>>'.

I don't really know what to do here. Any help would be appreciated since I rely on the deployment project to go live, and now it's blocking.

Thanks!

c# code pasteing

sjnaughton — Mon, 29 Dec 2008 05:00:00 GMT

This is just to mention that the c# code paste does not paste in the Generics part of code see this post here Validation shows me the errors in english and not in spanish compare davidebb post and my (sjnaughton) post and the OfType() method which is missing the <DataTypeAttribute>. I have manually pasted in the missing bite see example below:

protected void Page_Load(object sender, EventArgs e)
{
    TextBox1.ToolTip = Column.Description;

    SetUpValidator(RequiredFieldValidator1);
    SetUpValidator(CompareValidator1);
    SetUpValidator(RegularExpressionValidator1);
    SetUpValidator(RangeValidator1);
    SetUpValidator(DynamicValidator1);

    // fix for CompareValidator not getting custom message
    var dataType = Column.Attributes.OfType().FirstOrDefault();
    if (dataType != null)
        CompareValidator1.ErrorMessage = dataType.ErrorMessage;
}

If you look at the HTML you will see

var dataType = Column.Attributes.OfType<DATATYPEATTRIBUTE>().FirstOrDefault();

Note the section in BOLD ITALIC this seems to be treated as unkown HTML

Problems with runtime specification of generic type T in User Control

cchamberlain1976 — Fri, 14 Nov 2008 05:00:00 GMT

Hi,

I have a web user control that needs to populate itself using a generic object. The type of that generic object will need to be passed into the user control using a parameter.

The code I have tried is as follows, but the compiler fails stating: the type arguments for method 'GetQuestion<T>(GenericQuestion<T> Question)' cannot be inferred from the usage. Try specifying the type arguments. Any help would be greatly appreciated.

Regards

Chris Chamberlain

public partial class Controls_GenericQuestion : System.Web.UI.UserControl
{
private string _DataType;
private int _QuestionID = 0;

public int QuestionID
{
get { return _QuestionID; }
set { _QuestionID = value; }
}

public String DataType 
{ 
get { return _DataType; } 
set 
{ 
_DataType = value;
Type generic = typeof(GenericQuestion<>);
Type inputType = Type.GetType(_DataType);
Type[] typeArgs = { inputType };
Type genericType = generic.MakeGenericType(typeArgs);
GetQuestion<typeArgs>(Activator.CreateInstance(genericType));
}

public void GetQuestion<T>(GenericQuestion<T> genQuestion)
{
GenericQuestionMapper<T> mapper = new GenericQuestionMapper<T>();
genQuestion = mapper.GetInstance(_QuestionID);
/* Population code involving genQuestion */
}
}

Generic return type.. help needed

sashee — Thu, 23 Oct 2008 04:00:00 GMT

Hi:

I am trying my hand on generics and I was struck when I prepared a method that returns a generic type. Here is the sample:

    private M testmethod<T,M>(IList<T> request)
    {
        IDictionary<int, string> dict = new Dictionary<int, string>();
        foreach (testclass myclass in (IList<testclass>)request)
        {
            dict.Add(myclass.testint, myclass.teststr);
        }
        return dict;
    }

And I am calling above method like:

dict = testmethod<testclass, IDictionary<int, string>>(mylist);

So I want to pass a list of a particular classes and return a dictionary made of those class values.

I am sure, I am missing the right syntax somewhere. please help me.. Thanks in advance..

~sashee

Re: Typed ViewPage Using Generics Without Code Behind

koistya — Wed, 22 Oct 2008 04:00:00 GMT

You just have explicitly added Version, Culture and PublicKeyToken to my example though all they are optional as far as I know. Anyway I have also added them and have same issues with Intellisense: