In PHP, the case statement is used to match a specific value in the switch statement and execute the corresponding code block: case statement syntax: case value 1: code block; break; match the expression value and case value, if they match Execute the corresponding code block, and if there is no match, execute the default code block (if it exists). The break statement is used to jump out of case blocks to prevent unexpected code execution.
case statement in PHP
In PHP, the case
statement is used A control structure that matches the given value and executes the block code. It is typically used within a switch
statement to determine which specific block of code to execute.
Grammar
case
The syntax of the statement is as follows:
case 值1: // 要执行的代码块 break; case 值2: // 要执行的代码块 break; ... default: // 如果没有匹配的 case,要执行的代码块 break;
Working principle
In the switch
statement, the case
statement matches the given expression value. If the expression value matches any case
value, the corresponding code block is executed. If the expression value does not match any case
value, the default
code block is executed (if one exists).
break statement
break
statement is used to break out of the case
block and continue execution of the switch
statement code behind. It is very important to prevent unexpected code execution.
Example
The following example uses the case
statement to determine whether a given number is odd or even:
$number = 5; switch ($number) { case 0: echo "该数字是偶数。"; break; case 1: echo "该数字是奇数。"; break; default: echo "该数字既不是偶数也不是奇数。"; break; }
Here In this case, because the value of $number
is 5, it matches the case 1
statement and outputs: "The number is odd."
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