Php inline if else

Often you’d want to execute a statement if a certain condition is met, and a different statement if the condition is not met. This is what else is for. else extends an if statement to execute a statement in case the expression in the if statement evaluates to false . For example, the following code would display a is greater than b if $a is greater than $b , and a is NOT greater than b otherwise:

The else statement is only executed if the if expression evaluated to false , and if there were any elseif expressions — only if they evaluated to false as well (see elseif).

Note: Dangling else

In case of nested if — else statements, an else is always associated with the nearest if .

Despite the indentation (which does not matter for PHP), the else is associated with the if ($b) , so the example does not produce any output. While relying on this behavior is valid, it is recommended to avoid it by using curly braces to resolve potential ambiguities.

User Contributed Notes 10 notes

An alternative and very useful syntax is the following one:

statement ? execute if true : execute if false

Ths is very usefull for dynamic outout inside strings, for example:

print(‘$a is ‘ . ($a > $b ? ‘bigger than’ : ($a == $b ? ‘equal to’ : ‘smaler than’ )) . ‘ $b’);

This will print «$a is smaler than $b» is $b is bigger than $a, «$a is bigger than $b» if $a si bigger and «$a is equal to $b» if they are same.

If you’re coming from another language that does not have the «elseif» construct (e.g. C++), it’s important to recognise that «else if» is a nested language construct and «elseif» is a linear language construct; they may be compared in performance to a recursive loop as opposed to an iterative loop.

$limit = 1000 ;
for( $idx = 0 ; $idx < $limit ; $idx ++)
< $list []= "if(false) echo \" $idx ;\n\"; else" ; >
$list []= » echo \» $idx \n\»;» ;
$space = implode ( » » , $list );| // if . else if . else
$nospace = implode ( «» , $list ); // if . elseif . else
$start = array_sum ( explode ( » » , microtime ()));
eval( $space );
$end = array_sum ( explode ( » » , microtime ()));
echo $end — $start . » seconds\n» ;
$start = array_sum ( explode ( » » , microtime ()));
eval( $nospace );
$end = array_sum ( explode ( » » , microtime ()));
echo $end — $start . » seconds\n» ;
?>

This test should show that «elseif» executes in roughly two-thirds the time of «else if». (Increasing $limit will also eventually cause a parser stack overflow error, but the level where this happens is ridiculous in real world terms. Nobody normally nests if() blocks to more than a thousand levels unless they’re trying to break things, which is a whole different problem.)

There is still a need for «else if», as you may have additional code to be executed unconditionally at some rung of the ladder; an «else if» construction allows this unconditional code to be elegantly inserted before or after the entire rest of the process. Consider the following elseif() ladder:

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Php inline if else

elseif , as its name suggests, is a combination of if and else . Like else , it extends an if statement to execute a different statement in case the original if expression evaluates to false . However, unlike else , it will execute that alternative expression only if the elseif conditional expression evaluates to true . For example, the following code would display a is bigger than b , a equal to b or a is smaller than b :

if ( $a > $b ) echo «a is bigger than b» ;
> elseif ( $a == $b ) echo «a is equal to b» ;
> else echo «a is smaller than b» ;
>
?>

There may be several elseif s within the same if statement. The first elseif expression (if any) that evaluates to true would be executed. In PHP, it’s possible to write else if (in two words) and the behavior would be identical to the one of elseif (in a single word). The syntactic meaning is slightly different (the same behavior as C) but the bottom line is that both would result in exactly the same behavior.

The elseif statement is only executed if the preceding if expression and any preceding elseif expressions evaluated to false , and the current elseif expression evaluated to true .

Note: Note that elseif and else if will only be considered exactly the same when using curly brackets as in the above example. When using a colon to define if / elseif conditions, the use of elseif in a single word becomes necessary. PHP will fail with a parse error if else if is split into two words.

/* Incorrect Method: */
if ( $a > $b ):
echo $a . » is greater than » . $b ;
else if ( $a == $b ): // Will not compile.
echo «The above line causes a parse error.» ;
endif;

/* Correct Method: */
if ( $a > $b ):
echo $a . » is greater than » . $b ;
elseif ( $a == $b ): // Note the combination of the words.
echo $a . » equals » . $b ;
else:
echo $a . » is neither greater than or equal to » . $b ;
endif;

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PHP One Line If Statement

Decision-making is a critical part of any productive application. Conditional statements allow us to evaluate matching conditions and take action accordingly.

In PHP, decision-making constructs are implemented using if and if…else statements. Let us discuss using these statements and implement them in our programs.

PHP If Statement

The if statement in PHP allows you to check for a specific condition and perform a particular action if the state is true or false.

The syntax is shown below:

The program checks the condition in parenthesis. If the condition is true, it executes the code inside the curly braces.

We can illustrate this with an example as shown below:

The previous code checks if the value stored by the $age variable is greater than 18. If true, it prints the string “pass!!”.

The output is shown below:

PHP If…Else

In the previous example, we check for one condition and act if it is true. However, if the condition is false, the program does not do anything.

We can use an if…else block to specify the action if the condition is false.

The following syntax is provided:

The following example is shown:

In this example, we set the value of the $age variable to 10. Then, we use an if..else block to check if the age is greater than 18. If true, echo “Pass!!” else print “Denied!!”.

The previous code should return output as shown below:

PHP If…Elseif…Else

The other condition constructs in PHP is the if..elseif..else statement. This allows you to evaluate multiple conditions in a single block.

The following syntax is shown:

if ( test condition 1 ) {
// action if condition 1 is true
} elseif ( test condition 2 ) {
// action if condition 2 is true
} else {
// action if all are false
}

We can implement the following example:

If we run the previous code, we should get the following output:

PHP One Line If Statement

PHP provides us with a ternary operator to create a one-line if statement. It acts as a more concise version of an if…else statement.

The syntax is provided below:

Here’s the following example :

Both the ternary operator and an if…else statements work similarly. However, one is more verbose and readable, while the other is minimal and concise.

Conclusion

This tutorial covered conditional statements in PHP, including the ternary operator statement.

In addition, examples were provided to evaluate the matching conditions. Check other Linux Hint articles for more tips and tutorials.

About the author

John Otieno

My name is John and am a fellow geek like you. I am passionate about all things computers from Hardware, Operating systems to Programming. My dream is to share my knowledge with the world and help out fellow geeks. Follow my content by subscribing to LinuxHint mailing list

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One Line if Statement in PHP

if Statement in PHP
if. else Statement in PHP
if. elseif. else Statement in PHP
Ternary Operator to Provide the One Line if Statement in PHP

We as programmers often have to make decisions based on certain conditions and write code that is executed by the program if the conditions are met. The if statement is a decision-making statement available in all programming languages. We will learn about one line if statement & its alternatives in PHP.

PHP supports 4 differing types of Conditional Statements. All the conditional statements support logical operators inside the condition, such as && and || .

if Statement in PHP

The if statement will decide the flow of execution. It executes the code of the if block only when the condition matches. The program evaluates the code sequentially; if the first condition is true, all other conditions in the sequence will be ignored. This is true for all the conditional statements.

Syntax

 if(condition)   // Code to be executed  >

Example

php  $grade = "A";  if($grade = "A")  echo "Passed with Distinction";  > ?>

if. else Statement in PHP

It executes the code of the if block if the condition matches; otherwise, it executes the code of the else block. An alternative choice of an else statement to the if statement enhances the decision-making process.

Syntax

 if(condition)  // Code to be executed if condition is matched and true  > else   // Code to be executed if condition does not match and false  >

Example

php  $mark = 30;  if($mark >= 35)  echo "Passed";  > else   echo "Failed";  > ?>

if. elseif. else Statement in PHP

It Executes the code based on the matching condition. If no condition matches, the default code will be executed written inside the else block. It combines many if. else statements. The program will try to find out the first matching condition, and as soon as it finds outs matching condition, it executes the code inside it and breaks the if loop. If no else statement is given, the program will execute no code by default, and the code following the last elseif will be executed.

Syntax

 if (test condition 1)  // Code to be executed if test condition 1 is true  > elseif (test condition 2)  // Code to be executed if the test condition 2 is true and condition1 is false  > else  // Code to be executed if both conditions are false  >

Example

php  $mark = 45;  if($mark >= 75)  echo "Passed with Distinction";  > else if ($mark > 35 && $mark  75)   echo "Passed with first class";  > else   echo "Failed";  > ?>

Ternary Operator to Provide the One Line if Statement in PHP

It is an alternative to if. else because it provides an abbreviated way of writing the if. else statements. Sometimes it becomes difficult to read the code written using the ternary operator. Yet, developers use it because it provides a great way to write compact if-else statements.

Syntax

(Condition) ? trueStatement : falseStatement

Condition ? : A condition to check
trueStatement : A result if condition matches
falseStatement : A result if the condition does not match

The ternary operator selects the value on the left of the colon if the condition evaluates to be true and selects the value on the right of the colon if the condition evaluates to be false.

Let’s check the following examples to understand how this operator works:

Example:

php $mark = 38;  if($mark > 35)  echo 'Passed'; // Display Passed if mark is greater than or equal to 35  > else  echo 'Failed'; // Display Failed if mark is less than 35  > ?>

php $mark = 38;  echo ($mark > 35) ? 'Passed' : 'Failed'; ?>

There is no difference between both these statements at the byte code level. It writes compact if-else statements, nothing else. Bear in mind that ternary operators are not allowed in some code standards because it decreases the readability of code.

Shraddha is a JavaScript nerd that utilises it for everything from experimenting to assisting individuals and businesses with day-to-day operations and business growth. She is a writer, chef, and computer programmer. As a senior MEAN/MERN stack developer and project manager with more than 4 years of experience in this sector, she now handles multiple projects. She has been producing technical writing for at least a year and a half. She enjoys coming up with fresh, innovative ideas.

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