Implementation of PHP Cocktail sorting algorithm (code example)

PHP supports array deconstruction using the [] syntax since version 7.1, which can directly assign the value of the indexed array to variables; 2. Use the... operator to implement array expansion (similar to JavaScript's extension operator), which is used to merge arrays or transfer function parameters; 3. It can capture remaining elements with... operators, and simulate rest parameters; 4. Actual applications include processing CSV rows, function return value deconstruction and configuration merging; 5. Note... only applicable to index arrays, associative arrays should be used or array_merge(), and it does not support deep nested deconstruction of a single row, and needs to be processed in steps. Although modern PHP does not have the exact same deconstruction and extension syntax for JS, similar effects can be achieved through [] and...

To effectively handle missing or malformed $_GET parameters in PHP, input must be validated and cleaned first, provided default values, accessed data using type-safe methods, and failed gracefully in a user-friendly way. 1. Always check whether the parameters exist and verify their type and format, such as using isset() and filter_input() to ensure that the id is a positive integer; 2. Set safe default values for optional parameters, such as paging or sorting fields to avoid crashes due to missing; 3. Avoid direct access to $_GET, safe reading should be performed by encapsulating functions such as get_param() and get_int() combined with null merge operators; 4. When the parameters are invalid, the API should return 400 status code and JSON errors

preg_filter only returns replacement results when matched, otherwise it returns null, suitable for scenarios where verification and conversion are required; 1. The main difference between it and preg_replace is that it returns null instead of the original string when mismatch; 2. It is suitable for only retaining and converting data that conforms to the pattern; 3. When processing arrays, it automatically filters mismatch elements but retains key names, and can be reindexed with array_values; 4. Supports backreferences and moderate performance, suitable for form processing, URL rewriting and other scenarios; 5. When you need to keep all inputs, you should use preg_replace, while in the scenario of verification and conversion, preg_filter is more efficient and concise.

$_SERVER['REQUEST_METHOD'] is the core tool used in PHP to build RESTful APIs. It routes processing logic by judging HTTP request methods (such as GET, POST, PUT, DELETE). 1. Use the switch statement to perform corresponding operations based on the value of $_SERVER['REQUEST_METHOD']; 2. For PUT and DELETE requests, the input data needs to be manually parsed through file_get_contents('php://input'), because $_POST is not applicable; 3. Build a single entry point (such as index.php) to implement REST routing, supporting different parties

AlwaysusepreparedstatementswithparameterizedqueriestopreventSQLinjectionwhenhandling$_POSTdata.2.Validateandsanitizeinputearlybycheckingforrequiredfields,filteringdata,trimminglength,andrejectingunexpectedcharacters.3.Avoidrelyingonmysqli_real_escape

Using $_REQUEST will cause the order of input sources to be uncontrollable, which may cause conflicts between POST and GET parameters or be maliciously overwritten; 2. Due to the contain COOKIE data, attackers can perform security attacks such as privilege escalation by forging cookies; 3. It is easy for developers to ignore input verification sources, reducing code traceability and security; $_GET, $_POST or $_COOKIE should always be used to clearly specify the input source to improve the predictability, debugging and security of the code. If necessary, $_REQUEST can be disabled by configuring variables_order or request_order.

Use filter_input function to process POST input in PHP, because it can simultaneously implement secure access and filter verification, avoiding the risks of XSS and SQL injection caused by direct use of $_POST; 1. Use FILTER_SANITIZE_FULL_SPECIAL_CHARS to replace the deprecated FILTER_SANITIZE_STRING for special character escape; 2. Use FILTER_VALIDATE_EMAIL and FILTER_VALIDATE_INT to ensure the correct data format; 3. Arrays or multiple fields can be batch processed through encapsulation functions; 4. Pay attention to starting from PHP8.1

Extract nested logic to independent functions to reduce complexity and improve readability; 2. Use list comprehensions or generator expressions when applicable to make the code concise; 3. Flatten the data structure through iterative tools or data preprocessing to reduce nesting; 4. Use built-in library functions such as itertools to optimize loop structures; 5. Consider object-oriented or functional programming mode to encapsulate repetitive logic; the ultimate goal is to make the code intention clear through clear abstraction and naming, avoid understanding difficulties caused by deep nesting, thereby improving maintainability and readability.