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- how to connect a php framework to a mysql database
- ToconnectaPHPframeworktoMySQL,firstsetupthedatabasewithtoolslikephpMyAdminorthecommandlinebycreatingadatabaseanduserwithproperprivileges.Next,updatetheframework’sconfigurationfile—like.envinLaravel,database.phpinCodeIgniter,ordoctrine.yamlinSymfony—w
- PHP Tutorial . Backend Development 763 2025-07-09 00:42:21
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- How to call a namespaced function in PHP?
- There are three ways to call namespace functions in PHP: using fully qualified names, importing through use statements, or calling directly within the same namespace. 1. When using a fully qualified name, you need to add a backslash before the namespace, such as \Utilities\Text\format("hello"); 2. After importing through usefunctionUtilities\Text\format; you can directly call format("world"), or you can use alias such as usefunctionUtilities\Text\formatText; to call formatTe
- PHP Tutorial . Backend Development 767 2025-07-09 00:40:01
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- PHP strcmp vs == for string comparison
- To compare PHP strings, you should choose different methods according to your needs, and you cannot blindly use ==. Strictly compare it with ===, and strcmp() is used for dictionary order comparison. 1.==Unreliable, type conversion will cause unexpected results, such as '0e123'=='0' is true; 2.=== is the safest comparison method, the judgment is completely consistent and the type is not converted; 3.strcmp() is used to compare strings in dictionary order, returning -1, 0, and 1 to represent size relationships, and is case sensitive; 4. Safe scenarios must avoid ==, and performance === is better. Pay special attention to traps when comparing null or boolean values.
- PHP Tutorial . Backend Development 593 2025-07-09 00:38:32
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- How to parse a URL query string into variables with parse_str
- ToextractvariablesfromaURLquerystringinPHP,usetheparse_str()function.1.Passthequerystringandanoutputarraytoconvertparametersintoanassociativearray.2.ForfullURLs,firstextractthequerypartusingparse_url().3.Alwaysprovideasecondargumenttoavoidvariableinj
- PHP Tutorial . Backend Development 714 2025-07-09 00:35:40
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- php array remove duplicates from multidimensional array
- When dealing with PHP multi-dimensional array deduplication, you cannot use array_unique directly, and other methods are required. 1. Use serialize and unserialize to combine array_map to serialize the sub-array into a string and then deduplicate it, and then restore it to an array, which is suitable for two-dimensional arrays; 2. Customize the comparison function arrayUnique, which manually compares each element through traversal, which is highly flexible but less efficient; 3. Pay attention to the fact that the key names and order will affect the uniqueness judgment, and it is recommended to unify the structure or compare according to specific fields; 4. If deduplicate it according to a certain field (such as id), you can use a temporary array to record the existing field values, and only the items that appear for the first time are retained. The selection method should be determined based on the data structure and performance requirements.
- PHP Tutorial . Backend Development 955 2025-07-09 00:28:11
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- How to check if a PHP session is active?
- TocheckifaPHPsessionisactive,usesession_status()whichreturnsPHP_SESSION_ACTIVEifasessionisrunning.1.Usesession_status()===PHP_SESSION_ACTIVEforreliabledetection.2.Avoidrelyingonisset($_SESSION)asitcanbemisleading.3.ForlegacyPHPversionsbefore5.4,usese
- PHP Tutorial . Backend Development 834 2025-07-09 00:26:31
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- How to escape a string for a database query in PHP
- The most direct and effective way to prevent SQL injection is to use parameterized queries. 1. Use PDO preprocessing statements to safely bind variables by naming placeholders and execute() methods; 2. Use mysqli's preprocessing function to bind parameters through the placeholders and bind_param() methods; 3. Manual escape strings are not recommended because there are security risks and are outdated; 4. Always verify and filter user input, combined with the built-in security mechanism of the framework to enhance security.
- PHP Tutorial . Backend Development 491 2025-07-09 00:22:21
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- PHP prepared statement for DELETE query
- Performing DELETE operations using PHP's preprocessing statements prevents SQL injection and ensures that deletion is safe and controllable. 1. Establish a reliable database connection. It is recommended to use MySQLi or PDO; 2. Use placeholders (?) to write DELETE preprocessing statements and bind parameters through bind_param to ensure type matching; 3. Call execute() to perform deletion operations; 4. Optionally check affected_rows to confirm whether the deletion takes effect; 5. Pay attention to calling execute() multiple times during batch deletion, and explicitly close the statement to standardize the operation process.
- PHP Tutorial . Backend Development 991 2025-07-09 00:19:41
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- How to handle Date and Time operations in PHP?
- It is recommended to use the DateTime class for PHP processing date and time. 1. Use the DateTime class to replace old functions, with clear structure and support time zone settings; 2. Use DateTime to manage time and specify the target time zone before output; 3. Use DateInterval to calculate the time difference and obtain complete information such as year, month, and day; 4. Pay attention to avoid the influence of mixed use of date() functions, hard-coded time strings and daylight saving time.
- PHP Tutorial . Backend Development 268 2025-07-09 00:17:31
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- PHP header location with variables not working
- The main reasons for header jump failure include early output triggering, variable splicing errors and path configuration problems. 1. Output triggers in advance: Check whether there are echo/print/var_dump or file to introduce empty lines, and use ob_start() to buffer the output; 2. Variable splicing errors: Make sure that the variable has values ??and is formatted correctly, encode parameters with urlencode and print the verification URL; 3. Path or server problems: Confirm the path is correct and the domain name protocol matches, check the .htaccess/Nginx rewrite rules, manually test the URL access permissions and add exit termination script.
- PHP Tutorial . Backend Development 550 2025-07-09 00:14:00
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- How Do You Secure File Uploads in PHP?
- TosecurelyhandlefileuploadsinPHP,youmusttreateveryfileasapotentialthreatandimplementmultipleprotectivemeasures.1.LimitfiletypesusingawhitelistandverifytheactualextensionafterrenaminginsteadofrelyingonMIMEtypes.2.Renamefileswithuniqueidentifierstoprev
- PHP Tutorial . Backend Development 413 2025-07-09 00:08:40
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- how to loop through php array
- Common methods of traversing arrays by PHP include: 1. Use foreach to handle associative and indexed arrays, suitable for scenarios where indexes are not manually controlled; 2. Use for loops to traverse indexed arrays, suitable for situations where indexes need to be precisely controlled, but attention should be paid to avoid repeated calls to count() and non-continuous indexes; 3. While combined with each() for old versions of PHP traversal, but it has been deprecated in PHP8; 4.array_map is used to execute functions on each element and return a new array; 5.array_walk is used to directly modify the original array or execute side effects. Choosing the appropriate method according to the specific scenario can improve development efficiency and code readability.
- PHP Tutorial . Backend Development 926 2025-07-09 00:02:01
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- How Do You Pass Variables by Value vs. by Reference in PHP?
- InPHP,variablesarepassedbyvaluebydefault,meaningfunctionsorassignmentsreceiveacopyofthedata,whilepassingbyreferenceallowsmodificationstoaffecttheoriginalvariable.1.Whenpassingbyvalue,changestothecopydonotimpacttheoriginal,asshownwhenassigning$b=$aorp
- PHP Tutorial . Backend Development 152 2025-07-08 02:42:41
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- What are some key features introduced in PHP 8 ?
- PHP8 introduces a number of important new features, significantly improving performance, code readability and development experience. 1. JIT compilation improves execution speed, especially for CPU-intensive tasks, and is controlled through php.ini configuration; 2. Union types support more flexible type declarations, allowing direct definition of multiple parameter types; 3. Named parameters enhance the readability and security of function calls to avoid order errors; 4. Match expressions provide a more concise condition return method than switch, with strict comparison and non-penetration characteristics; 5. Constructor attribute improvement reduces boilerplate code, making class definition more concise; in addition, it also includes improvements such as throw expressions and attribute replacement annotations, making PHP8 more modern, powerful and easy to use overall. Although upgrades require investment,
- PHP Tutorial . Backend Development 423 2025-07-08 02:39:20
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