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PHP Comments

PHP is a server-side scripting language that is used to create dynamic web pages. It is an open-source language that is widely used by developers all over the world. PHP comments are an important feature of the language that allows developers to add notes and explanations to their code. In this article, we will discuss PHP comments in detail.

Brief Explanation of PHP Comments

Comments are lines of code that are not executed by the PHP interpreter. They are used to add notes and explanations to the code. Comments are ignored by the PHP interpreter and are not displayed in the output of the script. PHP supports two types of comments:

  • Single-line comments
  • Multi-line comments

Single-line Comments

Single-line comments start with two forward slashes (//) and continue until the end of the line. They are used to add comments to a single line of code. Here is an example:

  
    <?php
      // This is a single-line comment
      echo "Hello World!";
    ?>
  

In the above example, the comment is added to the first line of code. The PHP interpreter ignores the comment and executes the second line of code, which displays the text "Hello World!" in the output.

Multi-line Comments

Multi-line comments start with /* and end with */. They are used to add comments to multiple lines of code. Here is an example:

  
    <?php
      /*
      This is a multi-line comment
      It can span multiple lines
      */
      echo "Hello World!";
    ?>
  

In the above example, the comment is added to multiple lines of code. The PHP interpreter ignores the comment and executes the second line of code, which displays the text "Hello World!" in the output.

Code Examples

Here are some code examples that demonstrate the use of PHP comments:

Example 1: Single-line Comment

  
    <?php
      // This is a single-line comment
      echo "Hello World!"; // This is another single-line comment
    ?>
  

In the above example, two single-line comments are added to the code. The PHP interpreter ignores the comments and executes the second line of code, which displays the text "Hello World!" in the output.

Example 2: Multi-line Comment

  
    <?php
      /*
      This is a multi-line comment
      It can span multiple lines
      */
      echo "Hello World!";
    ?>
  

In the above example, a multi-line comment is added to the code. The PHP interpreter ignores the comment and executes the second line of code, which displays the text "Hello World!" in the output.

Example 3: Commenting Out Code

  
    <?php
      // echo "Hello World!";
      echo "Goodbye World!";
    ?>
  

In the above example, the first line of code is commented out using a single-line comment. This means that the PHP interpreter ignores the line of code and does not execute it. The second line of code is executed, which displays the text "Goodbye World!" in the output.

Conclusion

PHP comments are an important feature of the language that allows developers to add notes and explanations to their code. They are ignored by the PHP interpreter and are not displayed in the output of the script. PHP supports two types of comments: single-line comments and multi-line comments.

References

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