PHP英文单词汇总「PHP新手收藏」

1. Introduction

PHP (Hypertext Preprocessor) is a server-side scripting language that is used to develop web applications. It was created by Rasmus Lerdorf in 1994 and has become one of the most popular programming languages for web development. It is open source and free to use, and its syntax is similar to C and Perl. In this article, we will be discussing various PHP keywords and functions that every beginner should know when learning PHP.

2. Basic PHP keywords

2.1 Variables

Variables are used to store values in PHP. They are represented by the $ symbol followed by the variable name. Variable names are case-sensitive and must start with a letter or an underscore, followed by letters, numbers, or underscores.

$firstName = "John";
$lastName = "Doe";
$age = 25;

Important: Remember that variable names are case-sensitive and must start with a letter or an underscore.

2.2 Operators

Operators are used to perform operations on variables and values in PHP. Some of the most commonly used operators in PHP are:

Arithmetic operators (+, -, *, /, %)

Assignment operators (=, +=, -=, *=, /=, %=)

Comparison operators (==, ===, !=, <>, !==, <, >, <=, >=)

Logical operators (&&, ||, !)

Important: Remember that operators determine the order in which operations are performed.

2.3 Control structures

Control structures are used to control the flow of execution in PHP. Some of the most commonly used control structures in PHP are:

if...else statement:

$temperature = 30;
if ($temperature > 20) {
    echo "It's hot outside!";
} else {
    echo "It's cool outside!";
}

for loop:

for ($i = 0; $i <= 10; $i++) {
    echo $i;
}

Important: Remember that control structures are used to control the flow of execution in PHP.

3. PHP functions

Functions are blocks of code that can be reused throughout your PHP code. They are defined using the function keyword, followed by the function name and the code block enclosed in curly braces. Functions can accept parameters and return values.

Some of the most commonly used functions in PHP are:

echo function:

$name = "John";
echo "Hello, " . $name;

strlen function:

$text = "Hello, world!";
echo strlen($text); // Outputs 13

substr function:

$text = "Hello, world!";
echo substr($text, 0, 5); // Outputs "Hello"

Important: Remember that functions are blocks of code that can be reused throughout your PHP code.

4. Conclusion

PHP is one of the most popular server-side scripting languages for web development. In this article, we discussed various PHP keywords and functions that every beginner should know when learning PHP. By understanding these keywords and functions, you can start building your own PHP applications and taking your web development skills to the next level.