What does true mean in php function

True is a keyword in the PHP function, which represents the Boolean value 1, indicating that the result of a condition or expression is true. It can be used in PHP functions to determine whether the function execution is successful, and can also be used for Boolean Assignment of type variables to determine whether the test passes.

Operating system for this tutorial: Windows 10 system, PHP version 8.1, Dell G3 computer.

The meaning and use of true in the php function

First of all, true is a Boolean value, which indicates that the result of a condition or expression is true. In PHP, true is a keyword that represents the Boolean value 1. The opposite value is false, which represents the Boolean value 0. In PHP functions, true or false is usually used to judge control statements or conditional statements. For example:

if(true){
    echo '这个条件为真！';
}

The above code will output "This condition is true!".

In PHP functions, a true value is usually returned when the function executes successfully. For example, PHP's file_put_contents() function is used to write a string to a file. When the function is successfully executed, it returns a true value, otherwise it returns false. For example:

$content = "Hello World!";
$file = "test.txt";
if(file_put_contents($file, $content)){
    echo "写入成功！";
} else {
    echo "写入失败！";
}

The above code will write "Hello World!" to a file named "test.txt". If the writing is successful, the file_put_contents() function will return true, and the program will output "Writing successful!"; if the writing fails, the function will return false, and the program will output "Writing failed!".

In addition to being used to judge conditions and function return values, true can also be used in some other scenarios. For example, in the assignment of a Boolean variable, you can use true or false. For example:

$is_passed = true;
if($is_passed){
    echo "你通过了测试！";
} else {
    echo "你没有通过测试！";
}

The above code will output "You passed the test!". The $is_passed variable is assigned a value of true, which means you passed the test.

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