php else what does it mean

In PHP, else means "other". The else statement is a clause of the if statement. It must be used together with the if statement and cannot exist alone. The if statement can only perform operations when the judgment result is true, while the else statement extends the if statement and can execute the corresponding statement when the judgment result in the if statement is false. The syntax "if (judgment condition) {statement block 1;} else{statement block 2;}" and "if(condition 1){statement block 1;}elseif(condition 2){statement block 2;}else{statement block 3;}".

The operating environment of this tutorial: windows7 system, PHP8 version, DELL G3 computer

In php, else It means "other" and is the clause of the if statement.

if...else statement

The if statement can only perform operations on the situation where the judgment result is true. This is not true in many situations. In this case, it is not enough, so there are statements in the form of if...else. Different from the if judgment, the if...else statement not only performs operations on the situation where the judgment result is true, but can also perform corresponding operations on the situation where the judgment result is not true.

The else statement extends the if statement and can execute the corresponding statement when the value of the expression in the if statement is FALSE. Another thing to note is that the else statement is a clause of the if statement and must be used together with the if statement and cannot exist alone.

The syntax format of the if...else statement is as follows:

if (判断条件) {
    语句块 1;
} else {
    语句块 2;
}

In the above format, if the "judgment condition" is true, then execute "statement block 1"; otherwise, execute "statement Block 2". Both "Block 1" and "Block 2" can contain multiple statements. The same as the if statement, if both "Statement Block 1" and "Statement Block 2" contain only one statement, the curly brackets { } can be omitted, as follows:

if (判断条件)
    语句块 1;
else
    语句块 2;

if...else The execution flow of the statement is shown in the figure below:

Example: Use the rand() function to generate a random number $num, and then determine whether the random number is Even or odd number, the code is as follows:

<?php
    $num = rand(1,31);  //生成一个 1~31 之间的随机数
    if ($num % 2 == 0) {
        echo &#39;$num =&#39;.$num.&#39;, 是偶数！&#39;;
    } else {
        echo &#39;$num =&#39;.$num.&#39;, 是奇数！&#39;;
    }
?>

The running result is as follows:

$num =27, 是奇数！

if...elseif....else statement

if...elseif....else statement - execute different code blocks based on more than two conditions

Syntax

if (条件) {
  条件为 true 时执行的代码;
} elseif (condition) {
  条件为 true 时执行的代码;
} else {
  条件为 false 时执行的代码;
}

Example:

If the current time (HOUR) is less than 10, the following example will output "Have a good morning!", if the current time is less than 20, then output "Have a good day!". Otherwise, "Have a good night!" will be output:

<?php
    $t=date("H");
    if ($t<"10") {
      echo "Have a good morning!";
    } elseif ($t<"20") {
      echo "Have a good day!";
    } else {
      echo "Have a good night!";
    }
?>

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