8/19/2023 0 Comments Php switch case break continue![]() In this example I’ll show you how to use continue from loops and nested loops. You can always contact me if you’d like more detail on the project I describe. The way to handle this is really easy…both the break and continue statements in PHP have optional integer arguments where you can specify how many structures to break out of!ĭon’t worry, I’m not going to paste in my whole solution and let you find the interesting bits. I quickly realized that the break statement I placed to break out of the month search loop was only breaking out of the case statement! So when it went looking for the next month, it wouldn’t find it and as such would run the digit match routine! I found that the script would hit this every time, even though I placed it where it should only run if the month string wasn’t found. That was easy enough, but what I found that some users would enter a numeric month day, or day month. The routine I’m working on looks to see if the user entered a month if a particular code (EDD) has been entered into the field. I won’t bore you with the details, but suffice it to say, “Yay Reg Ex!” □ The issue is that the comments are a single string (meaning that users may enter several things into the same field (its a Meditech thing), and that this is free text. I’m currently working on a project that requires me to parse through comments entered into our Meditech Hospital Information System, looking for key phrases and performing certain actions based on these key phrases. Its one of those things that I don’t really think about when I’m banging out code, and that I can miss when I go back to see why things aren’t working. The statement list for a case can also be empty, which simply passes control into the statement list for the next case.One of the most frequent “gotchas” that I run into are breaking out of loops properly. If your condition is more complicated than a simple compare and/or is in a tight loop, a switch may be faster. In an elseif statement, the condition is evaluated again. ![]() In a switch statement, the condition is evaluated only once and the result is compared to each case statement. Thus, it is important not to forget break statements (even though you may want to avoid supplying them on purpose under certain circumstances). You would get the expected behavior (‘i equals 2’ would be displayed) only if $i is equal to 2. Here, if $i is equal to 0, PHP would execute all of the echo statements! If $i is equal to 1, PHP would execute the last two echo statements. If you don’t write a break statement at the end of a case’s statement list, PHP will go on executing the statements of the following case. PHP continues to execute the statements until the end of the switch block, or the first time it sees a break statement. Only when a case statement is found with a value that matches the value of the switch expression does PHP begin to execute the statements. without a break statement, ‘each’ of the lines will execute. You neglected to mention the need for the break statement. The default term is comparable to the else statement. As for the default:, it means that if none of the other conditions are satisfied, do the statements following the default. So, use break at the end of your case block to break out of the switch statement unless you want the following cases to be executed. If we didn’t use break, PHP would continue to execute the other conditions in the switch statement. Finally, we come to the break, which signals the end of the if like statement. After that colon, we have our statements to be executed. ![]() Instead, the case is followed by the conditional variable. However, we can see that we do not have to repeat that boring comparison operator over and over. The entire switch is implicitly using the = that we saw in the if statements earlier. ![]() The syntax is slightly different than an if statement. ![]() Example $x = 3 Ĭase 1: //this statement is the same as if($x = 1)Ĭase 2: //this statement is the same as if($x = 2)Ĭase 3: //this statement is the same as if($x = 3)Ĭase 4: //this statement is the same as if($x = 4)ĭefault: //this statement is the same as if $x does not equal the other conditions Whilst these statement constructs work well for testing a limited number of conditions they quickly become unwieldy when dealing with larger numbers of possible. The simple syntax of switch statements provide more readable code as opposed to using a lot of else if statements. If statements check one conditional, but switch statements can check for many different cases. As you use them, you will begin to realize why they are much more convenient that writing a whole lot of if statements or elseif statements. The PHP switch statement is pretty much a simplified way to write multiple if statements for one variable. ![]()
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