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You are currently viewing the Ternary Operator Statements tutorial, in the 'PHP' category.
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The use of Ternary Operators allows for nothing more than a cleaner, safer method of writing if...else statements, especially when placing statements inside other statements.
Take, for example, standard If/Else premises:
<?php
if ($var == "value1" || !$_REQUEST['action']){
$text = "STATEMENT1"; // if condition returns true
} else {
$text = "STATEMENT2"; // if codition returns false
}
echo($text);
?> |
In verbal form, the above code is executed as follows:
If the variable, $var, equals the invariant, value1 -- OR if action is not defined in the header as a HTTP Function -- STATEMENT1 is echoed. Conversely, if the condition returns false instead ( ... $var != "value1" || isset($_REQUEST['action']) ...) STATEMENT2 is echoed.
No problem.
However, yes, there is another way of writing this - we use the following general syntax for Ternary Operator statements:
| $output_var = (condition) ? Rslt_if_True : Rslt_if_False; |
Um, what? Let me explain.
The condition is being submitted for proof testing, hence the first conditional or ternary operator -- the question mark ("?") -- that immediately follows it. This operator preceeds the value of the output variable, $output_var, if the condition is TRUE - Rslt_If_True.
If the condition returns false, $output_var equals the portion of the string that follows the second ternary operator (the colon, ":") - Rslt_If_False.
Let's apply our initial example to the ternary operator syntax:
· $output_var = $text
· (condition) = ($var == "value1" || !$_REQUEST['action'])
· Rslt_If_True = STATEMENT1
· Rslt_If_False = STATEMENT2
Ergo, our initial if...else statement may be written as follows:
<?php
$text = ($var == "value1" || !$_REQUEST['action']) ? STATEMENT1 : STATEMENT2;
echo($text);
?>
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For those who have not yet been scared away, we will continue with "stacked" ternary operator statements (where one statement is placed inside another).
Firstly, our standard if...else statement:
<?php
$var = 2;
$global_var = "value1";
if($global_var == "value1"){
$result = 2;
} else {
$result = 3;
}
if ($var == $result){
$text = "STATEMENT1"; // if condition returns true
} else {
$text = "STATEMENT2"; // if codition returns false
}
echo($text);
?> |
Alas, we have two if/else statements, where the output of the latter is a direct (and dependent) function of the former's. Yuck.
The stacked statements, in ternary syntax, are written as follows:
<?php
$var = 2;
$global_var = "value1";
$text = ($var == (($global_var == "value1") ? 2 : 3)) ? STATEMENT1 : STATEMENT2;
echo("$text");
?> |
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