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Conditional statements
When you write code, you often need to perform different actions for different judgments.
You can use conditional statements in your code to accomplish this task.
Execute a block of code when the condition is true, and execute another block when the condition is not true Code
elseif statement
Use with if...else to execute a block of code when one of several conditions is trueIf...Else statement
If you want to execute some code when a certain condition is true , to execute other code when the condition is not true, please use if....else statement.
Syntax
if (condition) code to be executed if condition is true; else code to be executed if condition is false;
Example
If the current date is Friday, the following code will output "Have a nice weekend!", otherwise "Have a nice day!" will be output:
<html>
<body>
<?php
$d=
date
("D");
if ($d=="Fri")
echo
"Have a nice weekend!";
else
echo "Have a nice day!";
?>
</body>
</html>If you need to execute multiple lines of code when the condition is true or not, these lines of code should be included In curly braces:
<html>
<body>
<?php
$d=date("D");
if ($d=="Fri")
{
echo "Hello!<br />";
echo "Have a nice weekend!";
echo "See you on Monday!";
}
?>
</body>
</html>ElseIf statement
If you want to execute code when one of multiple conditions is true, use the elseif statement:
Syntax
if (condition) code to be executed if condition is true; elseif (condition) code to be executed if condition is true; else code to be executed if condition is false;
Example
If the current date is Friday, the following example will output "Have a nice weekend!", if it is Sunday, it will output "Have a nice Sunday!", otherwise it will output "Have a nice day!":
<html>
<body>
<?php
$d=date("D");
if ($d=="Fri")
echo "Have a nice weekend!";
elseif ($d=="Sun")
echo "Have a nice Sunday!";
else
echo "Have a nice day!";
?>
</body>
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