| 4. 3. 1. switch语句 |
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- An alternative to a series of else if is the switch statement.
- The switch statement allows you to choose a block of statements to run from a selection of code, based on the return value of an expression.
- The expression used in the switch statement must return an int or an enumerated value.
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The syntax of the switch statement is as follows. |
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switch (expression) {
case value_1 :
statement (s);
break;
case value_2 :
statement (s);
break;
.
.
.
case value_n :
statement (s);
break;
default:
statement (s);
}
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Failure to add a break statement after a case will not generate a compile error but may have more serious consequences because the statements on the next case will be executed. |
Here is an example of the switch statement: |
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public class MainClass {
public static void main(String[] args) {
int i = 1;
switch (i) {
case 1 :
System.out.println("One.");
break;
case 2 :
System.out.println("Two.");
break;
case 3 :
System.out.println("Three.");
break;
default:
System.out.println("You did not enter a valid value.");
}
}
}
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