


"Fatal error: Cannot Redeclare " - Troubleshooting PHP Function Duplication
Understanding the Error
The error "Fatal error: Cannot redeclare " indicates that a PHP function is being declared more than once within the same PHP script or within multiple included files.
Possible Causes and Solutions
- Function Declaration in Different Files: Ensure that the function is defined in only one PHP file. Search for other PHP files that may contain the same function declaration.
- Duplicate Declaration within Same File: Check for multiple instances of the function declaration within the same file. Ensure that the function is defined only once.
- Repeated Inclusion of Function File: Validate that the file containing the function definition is not being included twice in the script. Use include_once instead of include to prevent the file from being included multiple times.
Resolving the Issue
To resolve this error, follow these steps:
- Identify Duplicate Declarations: Use a code editor or search tool to locate all instances of the function declaration.
- Eliminate Duplicates: Remove any duplicate declarations from the PHP script or included files.
- Ensure Unique Function Name: Verify that the function name is unique within the scope of the script or files.
- Check for Repeated File Inclusion: If the function is defined in an included file, use include_once to prevent multiple inclusions.
Example: Applying the Solution
In the provided example, the error is likely caused by a repeated inclusion of the functions.php file. To resolve it:
include_once 'functions.php'; // Use include_once to include the file only once
The above is the detailed content of Why Am I Getting the 'Fatal error: Cannot Redeclare' Error in PHP?. For more information, please follow other related articles on the PHP Chinese website!

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