106: Overflowing an Integer Value in C#.NET

Encoding Denso QR Bar Code in C#.NET 106: Overflowing an Integer Value
Listing 106: Overflowing an Integer Value
QR-Code Creation In C#.NET
Using Barcode creation for Visual Studio .NET Control to generate, create QR Code JIS X 0510 image in VS .NET applications.
using System; public class Program { public static void Main() { // intMaxValue equals 2147483647 int n = intMaxValue; n = n + 1 ; SystemConsoleWriteLine(n); } }
Bar Code Generator In C#.NET
Using Barcode creation for VS .NET Control to generate, create barcode image in .NET applications.
The results of Listing 106 appear in Output 101
QR Code Creation In Visual Studio .NET
Using Barcode creation for ASP.NET Control to generate, create QR Code image in ASP.NET applications.
OUTPUT 101:
Make Quick Response Code In .NET
Using Barcode encoder for Visual Studio .NET Control to generate, create QR Code image in Visual Studio .NET applications.
The code in Listing 106 writes the value -2147483648 to the console However, placing the code within a checked block or using the checked option when running the compiler will cause the runtime to throw an exception of type SystemOverflowException The syntax for a checked block uses the checked keyword, as shown in Listing 107
Quick Response Code Generation In Visual Basic .NET
Using Barcode encoder for .NET framework Control to generate, create QR Code image in Visual Studio .NET applications.
Listing 107: A Checked Block Example
Painting Bar Code In Visual C#
Using Barcode encoder for VS .NET Control to generate, create barcode image in .NET framework applications.
using System; public class Program {
Barcode Creator In Visual C#
Using Barcode generation for .NET Control to generate, create barcode image in .NET applications.
10: Exception Handling
Making ANSI/AIM Code 39 In Visual C#.NET
Using Barcode maker for .NET framework Control to generate, create ANSI/AIM Code 39 image in .NET framework applications.
public static void Main() { checked { // intMaxValue equals 2147483647 int n = intMaxValue; n = n + 1 ; SystemConsoleWriteLine(n); } } }
Creating Code 128B In C#.NET
Using Barcode printer for .NET Control to generate, create Code 128 Code Set B image in Visual Studio .NET applications.
If the calculation involves only constants, then the calculation will be checked by default The results of Listing 107 appear in Output 102
Print DataMatrix In Visual C#.NET
Using Barcode encoder for Visual Studio .NET Control to generate, create Data Matrix image in Visual Studio .NET applications.
OUTPUT 102:
Paint ANSI/AIM Code 128 In VS .NET
Using Barcode drawer for Visual Studio .NET Control to generate, create Code-128 image in Visual Studio .NET applications.
Unhandled Exception: SystemOverflowException: Arithmetic operation resulted in an overflow at ProgramMain() in Programcs:line 12
Print Bar Code In VS .NET
Using Barcode encoder for .NET Control to generate, create barcode image in .NET framework applications.
In addition, depending on the version of Windows and whether a debugger is installed, a dialog may appear prompting the user to send an error message to Microsoft, check for a solution, or debug the application Also, the location information (Programcs:line X) will appear only in debug compilations compilations using the /Debug option of the Microsoft cscexe compiler The result is that an exception is thrown if, within the checked block, an overflow assignment occurs at runtime The C# compiler provides a command-line option for changing the default checked behavior from unchecked to checked C# also supports an unchecked block that truncates the data instead of throwing an exception for assignments within the block (see Listing 108)
Draw Barcode In Visual Studio .NET
Using Barcode encoder for VS .NET Control to generate, create barcode image in VS .NET applications.
Listing 108: An Unchecked Block Example
Bar Code Maker In Java
Using Barcode creation for Java Control to generate, create bar code image in Java applications.
using System; public class Program { public static void Main() { unchecked {
Draw EAN128 In VS .NET
Using Barcode maker for ASP.NET Control to generate, create UCC - 12 image in ASP.NET applications.
Summary
Data Matrix ECC200 Creator In VB.NET
Using Barcode encoder for .NET Control to generate, create Data Matrix 2d barcode image in .NET applications.
// intMaxValue equals 2147483647 int n = intMaxValue; n = n + 1 ; SystemConsoleWriteLine(n); } } }
Print USS Code 128 In .NET Framework
Using Barcode maker for ASP.NET Control to generate, create Code128 image in ASP.NET applications.
The results of Listing 108 appear in Output 103
Print EAN / UCC - 14 In .NET Framework
Using Barcode generation for Visual Studio .NET Control to generate, create GS1 128 image in Visual Studio .NET applications.
OUTPUT 103:
Create UPC Symbol In VS .NET
Using Barcode generation for ASP.NET Control to generate, create GTIN - 12 image in ASP.NET applications.
Even if the checked option is on during compilation, the unchecked keyword in the code in Listing 108 will prevent the runtime from throwing an exception during execution There are equivalent checked and unchecked expressions for cases where statements are not allowed, as is the case in a field initialize, for example:
UPC A Recognizer In .NET Framework
Using Barcode scanner for .NET framework Control to read, scan read, scan image in VS .NET applications.
int _Number = unchecked(intMaxValue + 1);
SUMMARY
Throwing an exception causes a significant performance hit A single exception causes lots of runtime stack information to be loaded and processed, data that would not otherwise be loaded, and it takes a considerable amount of time As pointed out in 4, use exceptions only to handle exceptional circumstances; APIs should provide mechanisms to check whether an exception will be thrown instead of forcing a particular API to be called in order to determine whether an exception will be thrown The next chapter introduces generics, a C# 20 feature that significantly enhances the code written in C# 10 In fact, it essentially deprecates any use of the SystemCollections namespace, which was formerly used in nearly every project
This page intentionally left blank
Generics
more sophisticated, you will need a better way to reuse and customize existing software To facilitate code reuse, especially the reuse of algorithms, C# includes a feature called generics Just as methods are powerful because they can take parameters, classes that take type parameters have significantly more functionality as well, and this is what generics enable Like their predecessor, templates, generics enable the definition of algorithms and pattern implementations once, rather than separately for each type However, C# generics are a type-safe implementation of templates that differs slightly in syntax and greatly in implementation from its predecessors in C++ and Java Note that generics were added to the runtime and C# with version 20
S YOUR PROJECTS BECOME
Covariance Contravariance
Generic Internals
C# Without Generics
Variance
Generic Methods
Generics
Nullable Modifier
Interface Base Class Struct/Class Multiple Constructor
Constraints
Using Defining Generic Types Benefits Naming Guidelines Interfaces Structs
11: Generics
C# without Generics
I will begin the discussion of generics by examining a class that does not use generics The class is SystemCollectionsStack, and its purpose is to represent a collection of objects such that the last item to be added to the collection is the first item retrieved from the collection (called last in, first out, or LIFO) Push() and Pop(), the two main methods of the Stack class, add items to the stack and remove them from the stack, respectively The declarations for the Pop() and Push() methods on the stack class appear in Listing 111