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- What are PSR standards and which ones are widely adopted in php?
- PSR represents the PHP standard recommendation in PHP, and is proposed by the PHP Framework Interoperability Group (PHP-FIG), which is used to unify code style, improve readability and collaboration efficiency. Its core goal is to promote compatibility between different frameworks and libraries, although not mandatory, but widely adopted. Common PSR standards include: 1.PSR-1: Basic coding specifications, specified for use
- PHP Tutorial . Backend Development 510 2025-07-10 13:15:21
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- PHP header location not working after echo
- The main reason for the failure of header('Location:...') is that it has output before it. 1. Once PHP starts output (such as echo, print, space or line break), the HTTP header is sent and cannot be modified; 2. Typical errors are echo first and then call the header; 3. Solutions include ensuring that there is no output before the header and putting redirection at the forefront of the script; 4. Alternative solutions can be used to jump JavaScript, HTMLmetarefresh or enable output buffering ob_start().
- PHP Tutorial . Backend Development 380 2025-07-10 13:07:41
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- how to get a random element from a php array
- TogetarandomelementfromaPHParray,useeitherarray_rand()orshuffle().Witharray_rand(),retrievearandomkeyandaccessitsvalue:1.Call$randomKey=array_rand($yourArray);and2.Gettheelementvia$randomElement=$yourArray[$randomKey];.Formultipleelements,passasecond
- PHP Tutorial . Backend Development 804 2025-07-10 12:59:51
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- PHP strlen vs mb_strlen for UTF-8 characters
- strlen is not suitable for counting UTF-8 characters because it calculates bytes rather than characters; 1. For example, "Hello" occupies 6 bytes, but only 2 characters; 2. The mblen function needs to specify UTF-8 encoding to count correctly; 3. Not specifying the encoding or the file is not UTF-8 may cause errors; 4. You need to select strlen or mb_strlen according to actual needs; 5. Pay attention to extended loading and encoding explicit declarations when using it.
- PHP Tutorial . Backend Development 457 2025-07-10 12:59:11
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- How to properly hash a string for a password in PHP
- ToproperlyhashpasswordsinPHP,usepassword_hash()withPASSWORD_DEFAULTbecauseitautomaticallyhandlessaltingandusesasecurealgorithmlikebcrypt.Alwaysstoretheresultinacolumnofatleast255characters.1.Avoidsettingafixedcostunlessnecessary;defaultsettingsareusu
- PHP Tutorial . Backend Development 622 2025-07-10 12:58:50
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- PHP header location not working
- Common causes and solutions for header jump failure: 1. You can only use the header before outputting content. If there is space or output content at the beginning of the file, it will cause failure. The solution is to ensure that there is no output before the header or buffer it with ob_start; 2. Header parameters such as wrong URL path or syntax will affect the jump. It is recommended to add exit immediately to terminate the subsequent code after writing the jump; 3. Browser cache may cause old data interference, so you should clear the cache or change the browser to test, and check the 302 response and Location header in the network request; 4. PHP configuration may hide error prompts, and you can temporarily turn on the error display to view "headersalreadysent" and other warnings. The order of investigation should be checked first
- PHP Tutorial . Backend Development 250 2025-07-10 12:57:51
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- How Do You Send Emails Using PHP?
- PHP can send emails, but you need to pay attention to the correct method. 1. Use the built-in mail() function to quickly realize basic mail sending, but depends on server configuration; 2. A more reliable way is to use SMTP libraries such as PHPMailer, which support authentication, attachments and HTML mail; 3. Common problems include wrong header format, mail entering the trash bin, lack of dependencies and error-free processing; 4. Small projects can use mail(), and it is recommended to use SMTP scheme for important functions. Ensure that the code includes an error handling mechanism to improve debugging efficiency and email sending success rate.
- PHP Tutorial . Backend Development 766 2025-07-10 12:51:01
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- Explain the Difference Between `break` and `continue` in PHP Loops
- InPHPloops,breakstopstheentireloopandproceedstothecodeafterit,whilecontinueskipsonlythecurrentiteration.1.Usebreaktoexitearlywhenaconditionismet,suchasfindingamatchorreachingalimit.2.Usecontinuetoskipcertainvaluesorcaseswithoutstoppingthewholeloop,li
- PHP Tutorial . Backend Development 364 2025-07-10 12:44:31
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- how to insert an element at a specific position in a php array
- In PHP, to insert elements at the specified location of the array, use the array_splice() function. This function allows one or more elements to be inserted in any index without affecting other elements. Its syntax is array_splice(&$inputArray,$offset,$length,$replacement), where $offset specifies the insertion position, $length is 0 means no elements are deleted, and $replacement is the element to be inserted; for example, after inserting 'grape' at index 1 of the array ['apple','banana','orange'], the result becomes ['apple','grape','apple']
- PHP Tutorial . Backend Development 636 2025-07-10 12:44:01
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- How to handle configuration management in a PHP project?
- Configuration management should unify the structure, distinguish the environment, and protect sensitive information in PHP projects. Specific practices include: 1. Use a unified configuration file structure, such as config/app.php, config/database.php and config/env.php to centrally manage configurations for different purposes; 2. Use environment variables (such as APP_ENV), and load the corresponding configuration in the initialization stage, and use getenv() or third-party libraries to read .env files; 3. Avoid submitting sensitive information to the code repository. Configurations should be dynamically injected through external files, environment variables or CI/CD, and ensure that the deployment script can automatically identify the configuration source.
- PHP Tutorial . Backend Development 706 2025-07-10 12:37:20
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- Why am I losing my PHP session after a redirect?
- Common causes of the problem include not starting the session correctly, not saving session data before redirection, or inconsistent session cookie configuration. 1. Ensure that session_start() is called at the top of each PHP file that requires session data, and there is no output interference; 2. Use session_write_close() to force the session data to be saved before redirection; 3. Set the path and domain name parameters of the session cookie through session_set_cookie_params() to ensure cross-page consistency.
- PHP Tutorial . Backend Development 244 2025-07-10 12:31:41
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- How do you handle file system operations in php securely?
- To safely handle file system operations in PHP, first of all, you need to verify and clean all user input, use basename() to extract file names, avoid directly allowing users to input paths, and check whether the input meets expectations through regular expressions; secondly, restrict files to access a secure directory, you can compare the allowable paths by using realpath() in the open_basedir configuration or code; thirdly, set correct file and directory permissions, recommend 0755 directory and 0644 file permissions, avoid using 0777; fourthly, use PHP built-in functions to process files to avoid executing shell commands; finally record and monitor file operation behavior to discover abnormal activities. These steps can effectively prevent unauthorized access and data loss
- PHP Tutorial . Backend Development 117 2025-07-10 12:21:40
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- How to start a session in PHP?
- To start a PHP session, you must first call the session_start() function, and it must be placed at the beginning of the script and before any output; secondly, store and retrieve data through the $_SESSION array, pay attention to check whether the variable exists and avoid storing sensitive information; finally, you must manually clear the $_SESSION array and call session_destroy() to delete the session cookies if necessary and redirect the user.
- PHP Tutorial . Backend Development 211 2025-07-10 12:18:21
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- PHP header location not working no error
- Common causes and solutions for header jump failure: 1. Use header before outputting content, check for unexpected output of spaces, echo or included files; 2. Continuing script execution causes jump to be invalid, and exit or die is required to terminate the program; 3. Server or framework restrictions, the framework redirection method should be used and the output compression module should be checked; 4. It is recommended to use a complete URL if the path is incorrect. Turning on output buffering, ensuring that there is no extra code after jumping, and clearing browser cache are also key measures.
- PHP Tutorial . Backend Development 387 2025-07-10 12:15:51
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