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- How to get the current session ID in PHP?
- The method to get the current session ID in PHP is to use the session_id() function, but you must call session_start() to successfully obtain it. 1. Call session_start() to start the session; 2. Use session_id() to read the session ID and output a string similar to abc123def456ghi789; 3. If the return is empty, check whether session_start() is missing, whether the user accesses for the first time, or whether the session is destroyed; 4. The session ID can be used for logging, security verification and cross-request communication, but security needs to be paid attention to. Make sure that the session is correctly enabled and the ID can be obtained successfully.
- PHP Tutorial . Backend Development 991 2025-07-13 03:02:31
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- how to find a key by its value in a php array
- There are three ways to find the corresponding keys of an array based on values in PHP: 1. Use the array_search function to directly find the first matching key, and return false if not found; 2. If there are multiple same values, you need to traverse the array custom function to obtain all matching keys; 3. Use the array_keys function and pass in the value parameter to return all matching keys at once. Note that array_search uses loose comparison by default. It is necessary to pass true to enable strict comparison. If it returns false, it means that it is not found. Be extra careful when judging.
- PHP Tutorial . Backend Development 913 2025-07-13 03:01:51
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- what are the advantages of using a php framework
- There are four main benefits of using PHP framework: improving development efficiency, unifying code structure, enhancing security, and providing community support. 1. The framework provides tools such as ORM, routing management, template engine, etc. to reduce duplicate labor and improve development speed; 2. Forced and standardized code structure and naming rules to facilitate team collaboration and maintenance; 3. Built-in security mechanisms such as SQL injection protection, XSS filtering, and CSRF protection to improve application security; 4. The mainstream framework has an active community and complete documents to facilitate problem solving and learning and use. Overall, although learning costs are required in the early stage, the efficiency, security and maintainability brought by the framework make it an indispensable development tool for medium and large projects.
- PHP Tutorial . Backend Development 997 2025-07-13 03:01:30
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- PHP get substring from a string
- To extract substrings from PHP strings, you can use the substr() function, which is syntax substr(string$string,int$start,?int$length=null), and if the length is not specified, it will be intercepted to the end; when processing multi-byte characters such as Chinese, you should use the mb_substr() function to avoid garbled code; if you need to intercept the string according to a specific separator, you can use exploit() or combine strpos() and substr() to implement it, such as extracting file name extensions or domain names.
- PHP Tutorial . Backend Development 511 2025-07-13 02:59:51
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- Can I store an object or an array in a PHP session?
- Yes,youcanstorebothobjectsandarraysinaPHPsession.Tostoreanarray,assignittoa$_SESSIONkey,suchas$_SESSION['user_preferences']=['theme'=>'dark','notifications'=>true,'language'=>'en'];,andaccessitlaterusing$_SESSION['user_preferences']['languag
- PHP Tutorial . Backend Development 479 2025-07-13 02:59:31
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- How to split a string into an array in PHP
- In PHP, the most common method is to split the string into an array using the exploit() function. This function divides the string into multiple parts through the specified delimiter and returns an array. The syntax is exploit(separator, string, limit), where separator is the separator, string is the original string, and limit is an optional parameter to control the maximum number of segments. For example $str="apple,banana,orange";$arr=explode(",",$str); The result is ["apple","bana
- PHP Tutorial . Backend Development 131 2025-07-13 02:59:10
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- How to store PHP sessions in a database?
- Store PHP sessions in the database to improve performance and facilitate management, especially in multi-server environments to realize session sharing. 1. Create a session table structure, including session_id, session_data and last_accessed fields; 2. Implement open(), close(), read($id), write($id, $data), destroy($id) and gc($max_lifetime) methods in the SessionHandlerInterface interface; 3. Register a custom handler and start the session; 4. Pay attention to locking mechanism, performance optimization, cleaning policies and security issues. By this
- PHP Tutorial . Backend Development 710 2025-07-13 02:56:41
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- How do you perform unit testing for php code?
- UnittestinginPHPinvolvesverifyingindividualcodeunitslikefunctionsormethodstocatchbugsearlyandensurereliablerefactoring.1)SetupPHPUnitviaComposer,createatestdirectory,andconfigureautoloadandphpunit.xml.2)Writetestcasesfollowingthearrange-act-assertpat
- PHP Tutorial . Backend Development 931 2025-07-13 02:54:31
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- How do PHP sessions work with AJAX requests?
- PHPsessionsworkwithAJAXrequestssimilarlytoregularpagerequestsbutrequireattentiontopersistence,blocking,andcross-domainissues.1.SessionsstartandpersistviathePHPSESSIDcookie,whichbrowsersautomaticallysendwithAJAXrequestsaslongassession_start()iscalledi
- PHP Tutorial . Backend Development 479 2025-07-13 02:53:50
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- Describe the Concept of CSRF and How to Protect Against it in PHP
- CSRF attacks are used to fake requests using the user's logged in identity. Specifically, the attacker induces users to access malicious websites, sends requests in the user's name without the user's knowledge, and performs non-intentional operations. A common way to prevent CSRF is to use the CSRFTToken mechanism, 1. Generate a unique random token; 2. Save the token in the Session and form hidden fields; 3. Compare whether the two are consistent when submitting. Other protection methods include checking the Referer header, setting the SameSiteCookie attribute, and introducing a verification code mechanism. Easy to ignore points include AJAX request not token, token generation is unsafe, and token storage into cookies incorrectly. The correct way is to only
- PHP Tutorial . Backend Development 306 2025-07-13 02:53:31
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- How to use PHP sessions with a different domain or cross-domain?
- The answer is: PHP native session is only available for single domain names by default, but can be shared across domains through manual intervention. 1. Explicitly pass the sessionID, pass it through URL parameters or custom header and set session_id in the target domain name; 2. Share the session storage backend, such as using Redis, Memcached or NFS shared directory; 3. Set the domain attribute of the cookie to be suitable for subdomain sharing; 4. Use advanced solutions such as OAuth, JWT or SSO to replace the direct sharing session to improve security and scalability. The above methods need to be combined with HTTPS and security control to prevent risks.
- PHP Tutorial . Backend Development 371 2025-07-13 02:46:11
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- php regex match anything until a character
- Matching "Arbitrary content up to a certain character" in PHP requires non-greed and forward-looking techniques. 1. Match until the colon can be preg_match('/^(.?):/',$str,$match), where ^ represents the beginning, (.?) non-greedy matches any character,: is the target character; 2. Use preg_match('/^(\D )/',$str,$match) to match the first number, and use preg_match('/^(.?)(?=\s)/',$str,$match); 3. Use forward-looking preg_match('/^(.?)(?=:)/',$str,$match) to avoid consumption of target words
- PHP Tutorial . Backend Development 798 2025-07-13 02:41:51
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- php get day number of year
- To get the current date is the day of the year, it can be implemented through PHP's date() function with the format character 'z'. 1. Use date('z') to directly obtain the day of the year. The return value starts from 0, so 1 is required to add to the actual number of days; 2. If you need to process the specified date, you can calculate it in combination with strtotime() or DateTime class passing date parameters; 3. date('z') has automatically considered the impact of leap years and does not require manual adjustment; 4. It is recommended to use DateTime for object-oriented scenarios to facilitate expansion and maintenance.
- PHP Tutorial . Backend Development 208 2025-07-13 02:41:31
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- How to pass a session variable to another page in PHP?
- In PHP, to pass a session variable to another page, the key is to start the session correctly and use the same $_SESSION key name. 1. Before using session variables for each page, it must be called session_start() and placed in the front of the script; 2. Set session variables such as $_SESSION['username']='JohnDoe' on the first page; 3. After calling session_start() on another page, access the variables through the same key name; 4. Make sure that session_start() is called on each page, avoid outputting content in advance, and check that the session storage path on the server is writable; 5. Use ses
- PHP Tutorial . Backend Development 775 2025-07-13 02:39:20
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