The debug_fwrite() WordPress PHP function is used to write contents to the file that is being used for debugging purposes.
Usage
Here’s a basic usage of debug_fwrite() function:
$debug_file = fopen("debug.txt", "w");
debug_fwrite($debug_file, "Debugging message");
fclose($debug_file);
In this example, the function writes the string “Debugging message” into the file “debug.txt”.
Parameters
- $fp (mixed): This parameter is required but not used.
- $message (string): This is the message to log. It is required.
More information
See WordPress Developer Resources: debug_fwrite()
This function is primarily used for debugging purposes. It’s similar to the function error_log(). Remember to close the file using fclose() after using debug_fwrite().
Examples
Basic Usage
Writing a simple message to the debugging file.
$debug_file = fopen("debug.txt", "w");
debug_fwrite($debug_file, "This is a test message");
fclose($debug_file);
Logging Variable Values
Logging the value of a variable to the debugging file.
$myVar = "Test value";
$debug_file = fopen("debug.txt", "w");
debug_fwrite($debug_file, "Value of myVar: " . $myVar);
fclose($debug_file);
Logging Array Values
Logging the values of an array to the debugging file.
$myArray = array("val1", "val2", "val3");
$debug_file = fopen("debug.txt", "w");
foreach($myArray as $value) {
debug_fwrite($debug_file, "Array value: " . $value);
}
fclose($debug_file);
Tracking Function Calls
Logging when a specific function is called.
function myFunction() {
$debug_file = fopen("debug.txt", "w");
debug_fwrite($debug_file, "myFunction() was called");
fclose($debug_file);
// rest of the function...
}
Error Logging
Logging an error message when an operation fails.
$operationSuccess = false; // Let's say an operation failed
if (!$operationSuccess) {
$debug_file = fopen("debug.txt", "w");
debug_fwrite($debug_file, "Operation failed at " . date("Y-m-d H:i:s"));
fclose($debug_file);
}