How can PHP developers efficiently troubleshoot issues related to file handling and variable types?

When troubleshooting issues related to file handling and variable types in PHP, developers can use built-in functions like `file_exists()`, `is_file()`, and `gettype()` to check file existence, file type, and variable type respectively. Additionally, using proper error handling techniques like try-catch blocks and using `var_dump()` to inspect variable values can help identify and resolve any issues efficiently.

// Check if a file exists
$file = 'example.txt';
if (file_exists($file)) {
    echo "File exists";
} else {
    echo "File does not exist";
}

// Check if a variable is of a specific type
$var = 10;
if (gettype($var) == 'integer') {
    echo "Variable is an integer";
} else {
    echo "Variable is not an integer";
}