Continue line in php

PHP: break, continue и goto

Часто бывает удобно при возникновении некоторых условий иметь возможность досрочно завершить цикл. Такую возможность предоставляет оператор break . Он работает с такими конструкциями как: while, do while, for, foreach или switch .

Оператор break может принимать необязательный числовой аргумент, который сообщает ему, выполнение какого количества вложенных структур необходимо завершить. Значением числового аргумента по умолчанию является 1, при котором завершается выполнение текущего цикла. Если в цикле используется оператор switch , то break/break 1 выходит только из конструкции switch .

\n"; break 1; /* Выход только из конструкции switch. */ case 10: echo "Итерация 10; выходим
\n"; break 2; /* Выход из конструкции switch и из цикла while. */ > > // другой пример for ($bar1 = -4; $bar1 < 7; $bar1++) < // проверка деления на ноль if ($bar1 == 0) < echo 'Выполнение остановлено: деление на ноль невозможно.'; break; >echo "50/$bar1 = ",50/$bar1,"
"; > ?>

Разумеется, иногда вы предпочли бы просто пропустить одну из итераций цикла, а не завершать полностью работу цикла, в таком случае это делается с помощью оператора continue .

continue

Для остановки обработки текущего блока кода в теле цикла и перехода к следующей итерации можно использовать оператор continue . От оператора break он отличается тем, что не прекращает работу цикла, а просто выполняет переход к следующей итерации.

Оператор continue также как и break может принимать необязательный числовой аргумент, который указывает на скольких уровнях вложенных циклов будет пропущена оставшаяся часть итерации. Значением числового аргумента по умолчанию является 1, при которой пропускается только оставшаяся часть текущего цикла.

"; continue; > echo "50/$bar1 = ",50/$bar1,"
"; > ?>

Обратите внимание: в процессе работы цикла было пропущено нулевое значение переменной $counter , но цикл продолжил работу со следующего значения.

goto

goto является оператором безусловного перехода. Он используется для перехода в другой участок кода программы. Место, куда необходимо перейти в программе указывается с помощью метки (простого идентификатора), за которой ставится двоеточие. Для перехода, после оператора goto ставится желаемая метка.

Простой пример использования оператора goto :

Оператор goto имеет некоторые ограничение на использование. Целевая метка должна находиться в том же файле и в том же контексте, это означает, что вы не можете переходить за границы функции или метода, а так же не можете перейти внутрь одной из них. Также нельзя перейти внутрь любого цикла или оператора switch . Но его можно использовать для выхода из этих конструкций (из циклов и оператора switch ). Обычно оператор goto используется вместо многоуровневых break .

"; > echo 'после цикла - до метки'; // инструкция не будет выполнена end: echo 'После метки'; ?>

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PHP continue Statement

When program flow comes across continue inside a loop, rest of the statements in current iteration of loop are skipped and next iteration of loop starts. The statement is commonly used in PHP conditions inside the loops, including , , , and .

PHP continue Statement

Introduction

The continue statement is one of the looping control keywords in PHP. When program flow comes across Continue inside a loop, rest of the statements in current iteration of loop are skipped and next iteration of loop starts. It can appear inside while, do while, for as well as foreach loop.

Syntax

In following example, continue statement will be executed every time while loop’s counter variable $x is even numbered. As a result odd numbers between 1 to 10 will be printed

Example

Output

This will produce following result −

The keyword continue can have an optional numeric argument to specify how many levels of inne loops are to be skipped. Default is 1

In following example continue keyword is used with a level argument in inner loop

Example

3) continue 2; echo "I : $i J : $j"."\n"; > echo "End of inner loop\n"; > ?>

Output

This will produce following result −

Start Of outer loop I : 1 J : 1 I : 1 J : 2 I : 1 J : 3 Start Of outer loop I : 2 J : 1 I : 2 J : 2 I : 2 J : 3 Start Of outer loop I : 3 J : 1 I : 3 J : 2 I : 3 J : 3 Start Of outer loop I : 4 J : 1 I : 4 J : 2 I : 4 J : 3 Start Of outer loop I : 5 J : 1 I : 5 J : 2 I : 5 J : 3

Difference between break and continue in PHP, Continue: 1. The break statement is used to jump out of a loop. The continue statement is used to skip an iteration from a loop: 2. Its syntax is -: break; Its syntax is -: continue; 3. The break is a keyword present in the language: continue is a keyword present in the language: 4. It can be used with loops ex-: for loop, …

Is there any line continuation character (& _) available in PHP?

I am dealing with long queries in PHP, so that I need to write it on multiple lines, but I don’t know if their any line continuation character is available in PHP.

I used the same in VB.NET as furnished below:

sql = "SELECT stoks,srate,prate,taxp," & _ "iname,suplier,icod FROM stock where iname='" & item_name.Text & "'" & _ "and suplier ='" & suplier.Text & " '" 

Is there any similar operation available in PHP, for denoting line continuation ?

In PHP, once you don’t close the quotation, you can write your code on multiple lines. Example:

$sql = "select stoks,srate,prate,taxp, iname,suplier,icod from stock where iname='".$item_name."' AND suplier ='".$suplier." '"; mysql_query($sql); 

PHP is different from the various versions of VB in that it uses a line termination character. (http://php.net/manual/en/language.basic-syntax.instruction-separation.php) As such there is no line continuation character required. Your long strings can just continue from line to line with no need to close the quotation.

$sql = "select stoks,srate,prate,taxp, iname,suplier,icod from stock where iname='".$item_name."' AND suplier ='".$suplier." '"; 

Or you can close the quotation block and connect it to another one using the period concatenation operator «.»

$sql = "select stoks,srate,prate,taxp," . "iname,suplier,icod from stock where iname='" . $item_name . "'" . " AND suplier ='" . $suplier . " '"; 

A third way to accomplish the same goal is to use the concatenation assignment operator. (http://php.net/manual/en/language.operators.string.php)

$sql = "select stoks,srate,prate,taxp,"; $sql .= "iname,suplier,icod from stock where iname='".$item_name."'"; $sql .= " AND suplier ='".$suplier." '"; 

There are other ways to accomplish the same idea, but these seem to be the most popular.

PHP doesn’t require it, but you can also concatenate strings in a similar fashion:

$myString = "Hello my name is john I am a super cool dude that likes cheese" . "I also like milk" . "I also like the number 8"; 

Current answers explain how to continue a concatenation. But what about any other expression, like a + b + c + . ; ?

You can use parenthesis to achieve expression continuation (which includes the concatenation). So, you can write expressions like:

# A chain of conditions $apply = ( $condition1 && $condition2 && $conditionn); # your example sql expression $sql = ( "select stoks,srate,prate,taxp," . "iname,suplier,icod from stock where iname='" . item_name.Text . "'" . "and suplier ='" . suplier.Text . " '"); 

PHP `continue` not working as expected, Teams. Q&A for work. Connect and share knowledge within a single location that is structured and easy to search. Learn more

The continue Statement in PHP

The continue statement is a conditional statement inside any loop to skip the current iteration based on the provided condition.

The loop will jump to the next iteration if it satisfies the condition with the continue statement.

The continue statement is commonly used in PHP conditions inside the loops, including while , do-while , for , and foreach loops .

The continue statement controls the flow to manipulate the code however you want.

Use the continue Statement in PHP while and do-while Loop

"; while($demo < 5) < if ($demo == 2) < echo "The number 2 is skipped
"; $demo++; continue; > echo "$demo 
"; $demo++; > //Do-While Loop $demo = 0; echo"
The output for do-while loop
"; do < echo "$demo
"; $demo++; if($demo==3)< echo"The number 3 is skipped
"; $demo++; continue; > > while ($demo

The output for while loop 0 1 The number 2 is skipped 3 4 The output for do-while loop 0 1 2 The number 3 is skipped 4 

As we can see, the numbers 2 and 3 were skipped from both loops because the condition satisfies, and the continue statement immediately jumps to the next iteration.

Use the continue Statement in PHP for and foreach Loop

For loop output is similar to the while loop; see example:

The iteration with number 2 will be skipped.

Similarly, in foreach , the continue statement can skip the iteration based on the particular value or key of the array. See example:

The iteration with the value Russia will be skipped.

Similarly, the continue statement can also be used in other conditions like else , elseif , and switch .

Use the continue Statement With Parameters in PHP

The continue takes one parameter used for the multiple level loops. See example.

"; for ($second=0;;$second++) < if ($second >= 2) continue 2; // This "continue" will apply to the "$first" loop echo "First Loop = $first Second Loop = $second"."
"; > echo "End
"; > ?> 

As you can see, the continue is in the second loop, but with parameter 2, if there is no parameter, the continue will directly work on the first loop.

Start Of First Loop First Loop = 0 Second Loop = 0 First Loop = 0 Second Loop = 1 Start Of First Loop First Loop = 1 Second Loop = 0 First Loop = 1 Second Loop = 1 Start Of First Loop First Loop = 2 Second Loop = 0 First Loop = 2 Second Loop = 1 

continue is a keyword in PHP, and it can’t be used as a variable name inside the loop in which the statement is used; otherwise, it will show an error.

Importance and Various Examples of Continue in PHP, In PHP the most common place where continue statements are used in the switch statement. Continue takes an optional numerical parameter which defines how many levels of internal loops the execution should skip and go to the end of. This means if the value is 1 then it skips to the end of the present loop.

PHP continue statement

The php continue statement is used to continue the loop. It continues the current flow of the program and skips the remaining code at the specified condition.

The continue statement is used within looping and switch control structure when you immediately jump to the next iteration.

The continue statement can be used with all types of loops such as — for, while, do-while, and foreach loop. The continue statement allows the user to skip the execution of the code for the specified condition.

Syntax

The syntax for the continue statement is given below:

Flowchart:

PHP Continue Example with for loop

In the following example, we will print only those values of i and j that are same and skip others.

PHP continue Example in while loop

In the following example, we will print the even numbers between 1 to 20.

 "; $i = 1; while ($i <=20) < if ($i %2 == 1) < $i++; continue; //here it will skip rest of statements >echo $i; echo "
"; $i++; >?>

Even numbers between 1 to 20: 2 4 6 8 10 12 14 16 18 20

PHP continue Example with array of string

The following example prints the value of array elements except those for which the specified condition is true and continue statement is used.

PHP continue Example with optional argument

The continue statement accepts an optional numeric value, which is used accordingly. The numeric value describes how many nested structures it will exit.

Look at the below example to understand it better:

PHP Continue, The PHP continue statement is used to continue the loop. It continues the current flow of the program and skips the remaining code at the specified condition. The continue statement is used within looping and switch control structure when you immediately jump to the next iteration. The continue statement can be used with …

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PHP Break and Continue

You have already seen the break statement used in an earlier chapter of this tutorial. It was used to «jump out» of a switch statement.

The break statement can also be used to jump out of a loop.

This example jumps out of the loop when x is equal to 4:

Example

PHP Continue

The continue statement breaks one iteration (in the loop), if a specified condition occurs, and continues with the next iteration in the loop.

This example skips the value of 4:

Example

Break and Continue in While Loop

You can also use break and continue in while loops:

Break Example

Continue Example

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