
- D Programming Basics
- D Programming - Home
- D Programming - Overview
- D Programming - Environment
- D Programming - Basic Syntax
- D Programming - Variables
- D Programming - Data Types
- D Programming - Enums
- D Programming - Literals
- D Programming - Operators
- D Programming - Loops
- D Programming - Decisions
- D Programming - Functions
- D Programming - Characters
- D Programming - Strings
- D Programming - Arrays
- D Programming - Associative Arrays
- D Programming - Pointers
- D Programming - Tuples
- D Programming - Structs
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- D Programming - Aliases
- D Programming - Mixins
- D Programming - Modules
- D Programming - Templates
- D Programming - Immutables
- D Programming - File I/O
- D Programming - Concurrency
- D Programming - Exception Handling
- D Programming - Contract
- D - Conditional Compilation
- D Programming - Object Oriented
- D Programming - Classes & Objects
- D Programming - Inheritance
- D Programming - Overloading
- D Programming - Encapsulation
- D Programming - Interfaces
- D Programming - Abstract Classes
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D Programming - Switch Statement
A switch statement allows a variable to be tested for equality against a list of values. Each value is called a case, and the variable being switched on is checked for each switch case.
Syntax
The syntax for a switch statement in D programming language is as follows −
switch(expression) { case constant-expression : statement(s); break; /* optional */ case constant-expression : statement(s); break; /* optional */ * you can have any number of case statements */ default : /* Optional */ statement(s); }
The following rules apply to a switch statement −
The expression used in a switch statement must have an integral or enumerated type, or be of a class type in which the class has a single conversion function to an integral or enumerated type.
You can have any number of case statements within a switch. Each case is followed by the value to be compared to and a colon.
The constant-expression for a case must be the same data type as the variable in the switch, and it must be a constant or a literal.
When the variable being switched on is equal to a case, the statements following that case executes until a break statement is reached.
When a break statement is reached, the switch terminates, and the flow of control jumps to the next line following the switch statement.
Not every case needs to contain a break. If no break appears, the flow of control falls through to subsequent cases until a break is reached.
A switch statement can have an optional default case, which must appear at the end of the switch. The default case can be used for performing a task when none of the cases is true. No break is needed in the default case.
Flow Diagram

Example
import std.stdio; int main () { /* local variable definition */ char grade = 'B'; switch(grade) { case 'A' : writefln("Excellent!" ); break; case 'B' : case 'C' : writefln("Well done" ); break; case 'D' : writefln("You passed" ); break; case 'F' : writefln("Better try again" ); break; default : writefln("Invalid grade" ); } writefln("Your grade is %c", grade ); return 0; }
When the above code is compiled and executed, it produces the following result −
Well done Your grade is B