116 lines
2.6 KiB
Markdown
116 lines
2.6 KiB
Markdown
---
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title: If-else Statement
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---
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## Introduction
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If/Else is a conditional statement where depending on the truthiness of a condition, different actions will be performed.
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> **Note:** The `{}` brackets are only needed if the condition has more than one action statement; however, it is best practice to include them regardless.
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## If Statement
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```
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<?php
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if (condition) {
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statement1;
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statement2;
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}
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```
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> **Note:** You can nest as many statements in an "if" block as you'd like; you are not limited to the amount in the examples.
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## If/Else Statement
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```
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<?php
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if (condition) {
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statement1;
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statement2;
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} else {
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statement3;
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statement4;
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}
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```
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> **Note:** The `else` statement is optional.
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## If/Elseif/Else Statement
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```
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<?php
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if (condition1) {
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statement1;
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statement2;
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} elseif (condition2) {
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statement3;
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statement4;
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} else {
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statement5;
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}
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```
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> **Note:** `elseif` should always be written as one word.
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## Nested If/Else Statement
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```
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<?php
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if (condition1) {
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if (condition2) {
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statement1;
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statement2;
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} else {
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statement3;
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statement4;
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}
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} else {
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if (condition3) {
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statement5;
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statement6;
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} else {
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statement7;
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statement8;
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}
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}
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```
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## Multiple Conditions
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Multiple conditions can be used at once with the "or" (||), "xor", and "and" (&&) logical operators.
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For instance:
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```
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<?php
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if (condition1 && condition2) {
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echo 'Both conditions are true!';
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} elseif (condition 1 || condition2) {
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echo 'One condition is true!';
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} else (condition1 xor condition2) {
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echo 'One condition is true, and one condition is false!';
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}
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```
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> **Note:** It's a good practice to wrap individual conditions in parens when you have more than one (it can improve readability).
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## Ternary Operators
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Another important option to consider when using short If/Else statements is the ternary operator.
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```php
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$statement=(condition1 ? "condition1 is true" : "condition1 is false");
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```
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## Alternative If/Else Syntax
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There is also an alternative syntax for control structures
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```php
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if (condition1):
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statement1;
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else:
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statement5;
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endif;
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```
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#### More Information:
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* <a href='http://php.net/manual/en/control-structures.alternative-syntax.php' target='_blank' rel='nofollow'>PHP Alternative syntax for control structures</a>
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* <a href="http://php.net/manual/en/control-structures.if.php" rel="nofollow">php.net control structures If Manual</a>
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* <a href="https://secure.php.net/manual/en/control-structures.elseif.php" rel="nofollow">php.net control structures Else If Manual</a> |