DirectCast How To Implement

Jan 14, 2012

i am using code to the value textbox2.text in the report and using the code like below [code]the textbox2 take various values in run time but when i run the code it display only the final value intermediated values are not displayed the whole situation is as follows.[code]

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C#'s Equivalent To .Net's DirectCast?

Apr 21, 2010

Does C# have an equivalent to VB.Net's DirectCast?I am aware that it has () casts and the 'as' keyword, but those line up to CType and TryCast.To be clear, these keywords do the following;CType/() casts: If it is already the correct type, cast it, otherwise look for a type converter and invoke it. If no type converter is found, throw an InvalidCastException.

TryCast/"as" keyword: If it is the correct type, cast it, otherwise return null.DirectCast: If it is the correct type, cast it, otherwise throw an InvalidCastException.

EDIT: After I have spelled out the above, some people have still responded that () is equivalent, so I will expand further upon why this is not true.

DirectCast only allows for either Narrowing or Widening conversions on inheritance tree, it does not support conversions across different branches like () does.ie: C#, this compiles and runs:

//This code uses a type converter to go across an inheritance tree
double d = 10;
int i = (int)d;

[code]....

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GetType() In DirectCast()?

Aug 4, 2011

I have a very simple problem where I have a MyList As List(Of MyBaseClass) but and a couple of MySub(ByVal Dummy As MyDerivedClassA)/MySub(ByVal Dummy As MyDerivedClassB). So I want to do the following ...

For Each MyInstance As MyBaseClass In MyList
MySub(DirectCast(MyInstance, MyInstance.GetType())
...

[code].....

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How To Use DirectCast Over Last Few Days

May 8, 2011

I learned how to use DirectCast over the last few days and it's really helped me. However, I have a similar issue, instead of textboxes I am looking at variables that are referenced in the class.To bring you all up to speed, I have four variables, a Boolean that dictates each of the 4 players I have playing my game. [code] I would assume it'd work similar to DirectCast but I am unsure. What I came up with caused errors: [code]

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Using Directcast As An Array?

Dec 1, 2009

I have 15 textboxes named MissionT1-15Is there a simple way to set all of their text to "Mission"?

missionT1.text="Mission"but for all of them with a loop?I saw something with directcast but wasn't able to make it work.

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Why Use TryCast Instead Of Directcast

Aug 28, 2010

Possible Duplicate: Why use TryCast instead of Directcast ? I want to know about the trycast and direct cast in vb.net. What is the difference between them?

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Difference Between DirectCast And TryCast?

Feb 23, 2010

What is the difference between DirectCast and TryCast? Can someone illustrate it in very simple words along with an example?

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Difference Between DirectCast() And CType() In .Net?

Jun 16, 2010

I am an experienced C/C++/C# programmer who has just gotten into VB.NET. I generally use CType (and CInt, CBool, CStr) for casts because it is less characters and was the first way of casting which I was exposed to, but I am aware of DirectCast and TryCast as well. Simply, are there any differences (effect of cast, performance, etc.) between DirectCast and CType? I understand the idea of TryCast.

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DirectCast & Null Values?

Jun 4, 2012

I have an SQL query that gets a max value so that I can decide the next value to use in an ID field. The code works fine when there's a matching result, but if the query returns Null, it throws a Specified Cast is Invalid error.This is the code I'm using:

LastID = DirectCast(SQLQuery.ExecuteScalar(), Integer)
What would be the proper way to check for a null value?

I suspect this is going to be one of those cases where within 2 minutes of posting myquestion, I finally hit upon the right combination of terms in Google to find what I'm looking for...

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DirectCast For Casting Without Conversion

Sep 4, 2009

I usually avoid VB's built-in conversion functions (CStr, CDate, CBool, CInt, etc.) unless I need to do an actual conversion. If I'm just casting, say from an object to a string, I normally use either DirectCast or TryCast, under the assumption that CStr, etc., are doing some extra stuff I don't need. But sometimes the DirectCast syntax is a little cumbersome, as in the following example.[code]SqlDataReader.Item returns an Object, which needs to be cast to a String. CStr is easier to read, type, and explain (IMO). My question is, does it matter which one I use? Should I just go with CStr (and CDate and CBool, etc.) and not worry about the extra work I assume those functions are doing? Is there any other downside to using these functions?

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Point Variable In DirectCast?

Sep 21, 2010

I was wondering if there was anyway for me to get the string value of a point variable so that I can compare it. I tried to do something like:

DirectCast("point" & number, Point).ToString

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VS 2008 CType Or DirectCast?

Dec 13, 2009

I turned option strict on, wich gave me some errors. The errors are quite easy to fix, but it seems like there are several ways of doing things. [code] 'previoustime' is declared as a TimeSpan, and the column "sluttid" is defined as a TimeSpan-column.Now, as far as I know, there are two ways of solving this; using CType and using DirectCast, like this: [code]

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Directcast & Ctype Differences With Enums?

Oct 13, 2009

Public Enum Fruit
Red_Apple = 1
Oranges
Ripe_Banana
End Enum
Private Sub InitCombosRegular()

[Code]...

Why does the Ctype work and the Directcast does not with the same syntax? Yet if I cast the selectedValue to an int before I DirectCast, then it works

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DirectCast / CType Are Common Function?

Oct 12, 2009

Does DirectCast, ctype, etc., are common function? Why it return type, and how do I used it? Is there others function where I need learn to be dot net expert?

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TryCast Fails Where DirectCast Works (.NET 4.0)

Aug 19, 2010

I find this behavior of TryCast in .NET 4.0 / VS 2010 rather confusing. In my understanding TryCast works like DirectCast, but will return Nothing instead of throwing an exception if a cast is not possible. VS 2010 / .NET 4

[Code]...

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.net - Casting DataTypes With DirectCast, CType, TryCast?

Apr 24, 2010

Ever since I moved from VB6 to VB.NET somewhere in 2005, I've been using CType to do casting from one data type to another. I do this because it is simply faster to type, used to exist in VB6 and I do not know why I have to be using DirectCast if there is apparently no difference between them.I use TryCast once in a while because I understand that sometimes casting can fail. I however cannot get the difference between CType and DirectCast.

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Performance (speed), Does Directcast Beat Ctype?

Jan 14, 2011

in terms of performance (speed), does directcast beat ctype?

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Programmatically Set The Object Type For A DirectCast Command?

Jan 16, 2009

I'm helping a colleague develop a "catch all" type error handler for some controls his application. What he wants to do is pass the object that has the error, and the type of that object, such a TextBox or ComboBox, and then call the DirectCast method within his handler to properly address the Text attribute within it. In general, the method is looking like this:

Protected Sub SpecialErrorHandler(ByVal TargetControl As Object, ByVal ControlType As String)
MessageBox.Show("Bad Juice: " & DirectCast(TargetControl, ControlType(ObjType)).Text)
End Sub

So far any attempts to do a type conversion within the DirectCast method (since it is expecting an object in the general signature) or to even pass in the a Type object properly set is not working.

Any ideas here, or is this one of those "Casting doesn't work that way." type scenarios?

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VS 2008 Directcast Control To Type Variable?

Jun 21, 2009

how can i cast a control to a type variable? heres the code i'm trying to use:

vb
Public Class form2Ex
Inherits Form2
Private list As Control = MyBase.CheckedListBox1
Private listType As Type

[Code]...

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Casting - DirectCast Not Accepting Valid Casts At Compiletime?

Oct 15, 2009

How come this is not a valid DirectCast:

Public Sub FB(OF T0 As IGH_Goo, T1 As IGH_Goo) _
(ByVal A As DataTree(Of T0), _
ByVal B As DataTree(Of T1))
Dim val_A As T1 = DirectCast(A.FirstItem, T1)
End Sub

[Code]...

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Error "DirectCast(err, SetupApiError) = InWow64 {-536870347}"

Nov 30, 2011

why i get the error "DirectCast(err, SetupApiError) = InWow64 {-536870347}" when running the code below? i get this error when it calls the SetupDiCallClassInstaller method on the line: Case SetupApiError.NoAssociatedClass To SetupApiError.OnlyValidateViaAuthenticode Throw New Win32Exception("SetupAPI error: " & DirectCast(err, SetupApiError).ToString)

Dim result As Boolean = SetupDiSetClassInstallParams(handle, diData, params, Marshal.SizeOf(params))
If result = False Then Throw New Win32Exception
result = SetupDiCallClassInstaller(DiFunction.PropertyChange, handle, diData)

[code]....

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Implement Something In VB?

Mar 14, 2011

How to implement such a feature in vb.net??

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Implement WCF In VB?

Apr 5, 2012

We have a vb.net application where we have implemented multithreading. We determined that we need to either implement .net remoting or WCF. After researching remoting in .NET on MSDN, Microsoft considers remoting legacy for .NET framework 4.0 and recommends using WCF instead. My question is: can we implement WCF functionality into our VB.NET application or do we need to rewrite the app from the ground up in WCF?

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Implement Threading In App?

Sep 1, 2010

I have a program that I would like to implement using Threading.I wand to load a form that takes a couple of minutes to open using threading.Here is my code

Imports System.Threading
Public Class frmAdjustments

Function LaunchForm() As Integer[code].....

I am new to .net programming and could use any suggestions you may have. I'm trying to grasp the concept of multithreading apps and would like to have both my main form (Adjustments) and the (frmNewAdjustments) form to load concurrently.Here is the error I receive with the code above: Overload resolution failed because no accessible 'New' can be called with these arguments:

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.net - Implement VB With Statement In C#?

Sep 3, 2010

How would you create an extension method which enables me to do the following (warning: exteme pseudo-code)...

class FooBar
{
Int32 Foo { get; set; }
String Bar { get; set; }
}
new FooBar().With(fb => new Func<FooBar, Object>(instance =>

[Code]...

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C# - How To Implement Of A Generic In .net

Mar 13, 2011

This is just a Translation question. But how do you write a the following C# code in vb.net My problem is that i don't know how to rewrite the this part of the generic T. C# code i want to translate

public static void ShouldEqual<T>(this T actualValue, T expectedValue) {Assert.AreEqual(expectedValue, actualValue); }

[Code]...

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C# - How To Implement Tracing In .net

Aug 7, 2009

I am implementing a tracing mechanism myself. Now what I'd like to know is what is the best way to implement this mechanism(I mean, the architecture).[code]But then I saw there is an TraceListener class that let's me implement Write and WriteLine methods. The big drawback is that both those methods allow only strings as arguments, and I'd want to be able to send a lot more info than strings. What should I do? Maybe my first ideia is the best?I do know there are a lot of tracing mechanisms like PostSharp and so, I'm just doing this for learning purposes!

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C# - Implement A Bitboard In .NET?

Mar 9, 2012

My Questions are: Is is possible to implement a bitboard in vb.net? Tutorial/Reference to do bitboard in VB?

C# answers are acceptable because it's not that hard to translate.

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C# - Implement The Equivalent Of SQL IN() Using .net?

Aug 4, 2010

In .net (c# or vb) expressions, how would you implement SQL's handy IN() functionality?i.e. value in (1, 2, 4, 7)rather than:

value = 1 or value = 2 or value = 4 or value = 7

There are obviously many ways, I'm looking for the most clean and simple!

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C# - When Should Implement IDisposable

Mar 12, 2010

What is the best practice for when to implement IDisposable? Is the best rule of thumb to implement it if you have one managed object in the class, or does it depend if the object was created in the class or just passed in? Should I also do it for classes with no managed objects at all?

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