What is the Difference between directcast and ctype?
- 1 Answers
- 8057 Views
- Wipro, I also Faced
- E-Mail Answers
Answer Posted / guest
Ans: The DirectCast keyword introduces a type conversion
operation. You use it the same way you use the CType
keyword, as the following example shows:
Dim Q As Object = 2.37 ' Requires Option Strict to be Off.
Dim I As Integer = CType (Q, Integer) ' Succeeds.
Dim J As Integer = DirectCast (Q, Integer) ' Fails.
Both keywords take an expression to be converted as the
first argument, and the type to convert it to as the second
argument. Both conversions fail if there is no conversion
defined between the data type of the expression and the
data type specified as the second argument.
The difference between the two keywords is that CType
succeeds as long as there is a valid conversion defined
between the expression and the type, whereas DirectCast
requires the run-time type of an object variable to be the
same as the specified type. If the specified type and the
run-time type of the expression are the same, however, the
run-time performance of DirectCast is better than that of
CType.
In the preceding example, the run-time type of Q is Double.
CType succeeds because Double can be converted to Integer,
but DirectCast fails because the run-time type of Q is not
already Integer.
DirectCast throws an InvalidCastException error if the
argument types do not match.
| Is This Answer Correct ? | 4 Yes | 4 No |
Post New Answer View All Answers
Why do we use static class in c#?
What is a generic in c#?
What is a verbatim string literal and why do we use it?
Is string immutable in c#?
Is c# or c++ better for games?
What is the main usage of keyword “virtual†? How does it work for a method or property?
What is difference between int and int in c#?
What are the 3 types of comments in c#?
What is difference between constants and readonly in c#?
What is a concrete class in c#?
What are actions in c#?
Suppose you have already existing application with Visual Studio 6 (VB 6, InterDev 6) and this application utilizes Windows 2000 COM+ transaction services. With this example how can you approach migrating this application to .NET?
What is null character in string?
How is the syntax written to inherit from a class in C#?Give an example ?
Does a class need a constructor c#?
