A switch statement is more efficient than a set of nested if statements. No two case constants in the same switch can have identical values.ģ. That is, the switch looks only for a match between the value of the expression and one of its case constants.Ģ. The switch differs from the if statements in the sense that switch can only test for equality, whereas if can evaluate any type of logical expression. Please enter a character Features of the switch statement:ġ. This is because after p~inting Apple, control will continue executing another case In above example, if the value of k is ‘a’, it will print: Look at the following example: Here, we have removed all break statementsĭefault: (“Please enter a character”) If the value of k is neither ‘a’ nor ‘b’, then control will execute default statement displaying “Please enter a character” on the screen. This means that when case is true, then its statements are executed followed by other case statements until control encounters break statement. it will also print Bat, even though the value of k is ‘a’. If break is not included, control will also execute the case statement following it i.e. break after takes the control out of the switch statement. If the value of k is ‘a’, then Apple will be printed on the screen. In above example, the control will jump to respective statement depending on the value of the variable k. It keeps on executing all the statements of each case construct one after the other until a break is encountered or switch gets over.ĭefault : (“Please enter a character”) Note: When the statement of any case is executed and we forget to place break, then control will go into following case construct and executes its statements also. If no default is present and no match is found control jumps to the statements following switch command. If no matches are found and a default is present, the group of statements associated with default will be executed. break statement is for exiting from switch construct. When the match is found, the corresponding group of statements between the case and break will be executed. The case statement works by evaluating the expression and then scanning down the case statements until a match is found. Next is a required completes the case statement. The parentheses contain expression which may be a byte, a char, a short, or an int. There's no need to preemptively save the result in a variable either.The keyword switch begins the switch construct. Without having to worry about the function being re-evaluated for every case. I think this fact needs a little bit more attention, so here's an example: The difference between a series of if statements and the switch statement is that the expression you're comparing with, is evaluated only once in a switch statement. This is listed in the documentation above, but it's a bit tucked away between the paragraphs. Getting Started Introduction A simple tutorial Language Reference Basic syntax Types Variables Constants Expressions Operators Control Structures Functions Classes and Objects Namespaces Enumerations Errors Exceptions Fibers Generators Attributes References Explained Predefined Variables Predefined Exceptions Predefined Interfaces and Classes Predefined Attributes Context options and parameters Supported Protocols and Wrappers Security Introduction General considerations Installed as CGI binary Installed as an Apache module Session Security Filesystem Security Database Security Error Reporting User Submitted Data Hiding PHP Keeping Current Features HTTP authentication with PHP Cookies Sessions Dealing with XForms Handling file uploads Using remote files Connection handling Persistent Database Connections Command line usage Garbage Collection DTrace Dynamic Tracing Function Reference Affecting PHP's Behaviour Audio Formats Manipulation Authentication Services Command Line Specific Extensions Compression and Archive Extensions Cryptography Extensions Database Extensions Date and Time Related Extensions File System Related Extensions Human Language and Character Encoding Support Image Processing and Generation Mail Related Extensions Mathematical Extensions Non-Text MIME Output Process Control Extensions Other Basic Extensions Other Services Search Engine Extensions Server Specific Extensions Session Extensions Text Processing Variable and Type Related Extensions Web Services Windows Only Extensions XML Manipulation GUI Extensions Keyboard Shortcuts ? This help j Next menu item k Previous menu item g p Previous man page g n Next man page G Scroll to bottom g g Scroll to top g h Goto homepage g s Goto search
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