barcode with vb.net C# 30: A Beginner s Guide in C#.NET

Generating Code128 in C#.NET C# 30: A Beginner s Guide

C# 30: A Beginner s Guide
Paint Code 128A In C#.NET
Using Barcode printer for .NET Control to generate, create Code 128A image in .NET framework applications.
Code 128B Decoder In C#
Using Barcode decoder for VS .NET Control to read, scan read, scan image in .NET framework applications.
To create a fixed-size buffer, use this form of fixed: fixed type buf-name[size]; Here, type is the data type of the array, buf-name is the name of the fixed-size buffer, and size is the number of elements in the buffer Fixed-size buffers can be specified only inside a struct As stated at the outset of this section, the creation and use of unsafe code is an advanced topic, and there are more issues involved with its creation than are discussed here If writing unsafe code will be a part of your programming future, then you will need to study it further
Bar Code Drawer In C#.NET
Using Barcode maker for .NET Control to generate, create bar code image in Visual Studio .NET applications.
Recognizing Barcode In Visual C#
Using Barcode scanner for Visual Studio .NET Control to read, scan read, scan image in Visual Studio .NET applications.
Attributes
USS Code 128 Creator In Visual Studio .NET
Using Barcode drawer for ASP.NET Control to generate, create Code 128A image in ASP.NET applications.
Making Code 128 In Visual Studio .NET
Using Barcode encoder for VS .NET Control to generate, create Code 128 Code Set C image in .NET applications.
C# allows you to add declarative information to a program in the form of an attribute An attribute defines additional information that is associated with a class, structure, method, and so on For example, you might define an attribute that determines the type of button that a class will display Attributes are specified between square brackets, preceding the item they apply to You can define your own attribute or use attributes defined by C# Although creating your own attributes is a topic that is beyond the scope of this book, it is quite easy to use two of C# s built-in attributes: Conditional and Obsolete They are examined in the following sections
ANSI/AIM Code 128 Creator In Visual Basic .NET
Using Barcode generation for VS .NET Control to generate, create ANSI/AIM Code 128 image in VS .NET applications.
Encode Code-39 In C#
Using Barcode generator for .NET Control to generate, create Code-39 image in .NET applications.
The Conditional Attribute
Paint Data Matrix 2d Barcode In C#.NET
Using Barcode printer for Visual Studio .NET Control to generate, create DataMatrix image in .NET applications.
Generating Linear Barcode In Visual C#
Using Barcode creator for .NET Control to generate, create Linear Barcode image in Visual Studio .NET applications.
The attribute Conditional is perhaps C# s most interesting attribute It allows you to create conditional methods A conditional method is invoked only when a specific symbol has been defined via #define Otherwise, the method is bypassed Thus, a conditional method offers an alternative to conditional compilation using #if To use the Conditional attribute, you must include the SystemDiagnostics namespace Let s begin with an example:
Code 128 Printer In Visual C#
Using Barcode drawer for Visual Studio .NET Control to generate, create Code 128C image in Visual Studio .NET applications.
Encode EAN-8 Supplement 5 Add-On In Visual C#
Using Barcode generation for VS .NET Control to generate, create GTIN - 8 image in .NET applications.
// Demonstrate the Conditional attribute #define TRIAL using System; using SystemDiagnostics; class Test { [Conditional("TRIAL")] Trial( ) is executed only if TRIAL is defined void Trial() { ConsoleWriteLine("Trial version, not for distribution"); } [Conditional("RELEASE")] Release( ) is executed only if RELEASE is defined void Release() { ConsoleWriteLine("Final release version"); }
Bar Code Decoder In Java
Using Barcode Control SDK for BIRT reports Control to generate, create, read, scan barcode image in BIRT reports applications.
Code 39 Extended Encoder In Objective-C
Using Barcode creation for iPad Control to generate, create Code 39 Full ASCII image in iPad applications.
15:
Reading Code 3 Of 9 In Visual Basic .NET
Using Barcode scanner for Visual Studio .NET Control to read, scan read, scan image in .NET framework applications.
Creating Bar Code In Visual Studio .NET
Using Barcode encoder for ASP.NET Control to generate, create bar code image in ASP.NET applications.
The Preprocessor, RTTI, Nullable Types, and Other Advanced Topics
Bar Code Drawer In None
Using Barcode generation for Font Control to generate, create barcode image in Font applications.
Encode Data Matrix ECC200 In Java
Using Barcode generator for Java Control to generate, create ECC200 image in Java applications.
static void Main() { Test t = new Test(); tTrial(); // call only if TRIAL is defined tRelease(); // called only if RELEASE is defined } }
Creating Bar Code In VS .NET
Using Barcode creation for Reporting Service Control to generate, create bar code image in Reporting Service applications.
GTIN - 128 Drawer In Visual Studio .NET
Using Barcode creation for Reporting Service Control to generate, create EAN / UCC - 13 image in Reporting Service applications.
The output from this program is shown here:
Trial version, not for distribution
Let s look closely at this program to understand why this output is produced First notice that the program defines the symbol TRIAL Next, notice how the methods Trial( ) and Release( ) are coded They are both preceded with the Conditional attribute, which has this general form: [Conditional symbol] where symbol is the symbol that determines whether the method will be executed This attribute can be used only on methods If the symbol is defined, then when the method is called, it will be executed If the symbol is not defined, then the method is not executed Inside Main( ), both Trial( ) and Release( ) are called However, only TRIAL is defined Thus, Trial( ) is executed The call to Release( ) is ignored If you define RELEASE, then Release( ) will also be called If you remove the definition for TRIAL, then Trial( ) will not be called Conditional methods have a few restrictions: They must return void; they must be members of a class or structure, not an interface; and they cannot be preceded with the override keyword
The Obsolete Attribute
[Obsolete "message"]
The SystemObsolete attribute lets you mark a program element as obsolete It has two basic forms The first is:
Here, message is displayed when that program element is compiled Here is a short example:
// Demonstrate the Obsolete attribute using System; public class Test { [Obsolete("Use MyMeth2, instead")] public static int MyMeth(int a, int b) { return a / b; }
Copyright © OnBarcode.com . All rights reserved.