Powershell - Switch Statement


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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 case.

Syntax

The syntax of enhanced for loop is −

switch(<test-value>) {
   <condition> {<action>} 
      break; // optional
   <condition> {<action>} 
      break; // optional
   <condition> {<action>} 
      break; // optional
}

The following rules apply to a switch statement −

  • The variable used in a switch statement can only be any object or an array of objects.

  • You can have any number of case statements within a switch. Each case is followed by optional action to be performed.

  • The value 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 will execute 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 will fall through to subsequent cases until a break is reached.

Flow Diagram

Switch Statement

Example 1

Example of Switch statment without break statment.

switch(3){
   1 {"One"}
   2 {"Two"}
   3 {"Three"}
   4 {"Four"}
   3 {"Three Again"}
}

This will produce the following result −

Output

Three
Three Again

Example 2

Example of Switch statment with break statment.

switch(3){
   1 {"One"}
   2 {"Two"}
   3 {"Three"; break }
   4 {"Four"}
   3 {"Three Again"}
}

This will produce the following result −

Output

Three

Example 3

Example of Switch statment with array as input.

switch(4,2){
   1 {"One"}
   2 {"Two"}
   3 {"Three"; break }
   4 {"Four"}
   3 {"Three Again"}
}

This will produce the following result −

Output

Four
Two
powershell_conditions.htm
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