Shulou(Shulou.com)06/01 Report--

In this article, the editor introduces in detail "how to use the conditional instruction of C#". The content is detailed, the steps are clear, and the details are handled properly. I hope that this article "how to use the conditional instruction of C#" can help you solve your doubts. Let's follow the editor's train of thought to learn new knowledge.

Conditional instruction

You can use the # if directive to create a conditional directive. Conditional instructions are used to test whether the symbol is true. If true, the compiler executes the code between # if and the next instruction.

Syntax for conditional instructions:

# if symbol [operator symbol]...

Where symbol is the name of the symbol to be tested. You can also use true and false, or place negative operators before symbols.

Common operators are:

= (equal to)

! = (not equal to)

& (and)

| | (or)

You can also group symbols and operators in parentheses. Conditional directives are used to compile code when debugging a version or when compiling a specified configuration. A conditional instruction that begins with a # if instruction must be explicitly terminated with a # endif instruction.

The following program demonstrates the use of conditional instructions:

# define DEBUG

# define VC_V10

Using System

Public class TestClass

{

Public static void Main ()

{

# if (DEBUG & &! VC_V10)

Console.WriteLine ("DEBUG is defined")

# elif (! DEBUG & & VC_V10)

Console.WriteLine ("VC_V10 is defined")

# elif (DEBUG & & VC_V10)

Console.WriteLine ("DEBUG and VC_V10 are defined")

# else

Console.WriteLine ("DEBUG and VC_V10 are not defined")

# endif

Console.ReadKey ()

}

}

When the above code is compiled and executed, it produces the following results:

DEBUG and VC_V10 are defined has read this, the article "how to use the conditional instructions of C#" has been introduced. If you want to master the knowledge points of this article, you still need to practice and use it yourself. If you want to know more about related articles, welcome to follow the industry information channel.

Welcome to subscribe "Shulou Technology Information " to get latest news, interesting things and hot topics in the IT industry, and controls the hottest and latest Internet news, technology news and IT industry trends.