current location：Home > Technical Articles > Daily Programming > PHP Knowledge
- Direction：
- All web3.0 Backend Development Web Front-end Database Operation and Maintenance Development Tools PHP Framework Daily Programming WeChat Applet Common Problem Other Tech CMS Tutorial Java System Tutorial Computer Tutorials Hardware Tutorial Mobile Tutorial Software Tutorial Mobile Game Tutorial
- Classify：
- PHP tutorial MySQL Tutorial HTML Tutorial CSS Tutorial
-
- how to pad a php array to a certain size
- ToensureaPHParrayhasanexactsize,useacombinationofarray_slice()andarray_pad().1.First,slicethearraytothetargetsizetoremoveexcesselements.2.Then,padtheslicedarraytoensureitmeetsthedesiredlength.Thismethodworksforbothtrimmingandextendingarrays,thoughpad
- PHP Tutorial . Backend Development 740 2025-07-04 02:00:37
-
- php calculate time difference in minutes
- Calculate the minute difference between two times in PHP by the following methods: 1. Use DateTime and DateInterval: Create two DateTime objects and call the diff() method to get the interval, and then convert it into minutes. It is suitable for scenes with span of days and clear logic; 2. Use timestamp subtraction: Use strtotime to convert to timestamp and calculate the difference and get the absolute value, which is suitable for quick and easy calculations, but pay attention to format and time zone issues; 3. Handle time zone differences: Use DateTimeZone to explicitly define the time zone and convert it to the same time zone for comparison to ensure the accuracy of the real time difference; In addition, it is recommended to use the abs() function when processing negative results, and at the same time the input format is also
- PHP Tutorial . Backend Development 355 2025-07-04 01:57:12
-
- how to convert php array to json
- In PHP, you can convert arrays to JSON format using the json_encode function. 1. Directly call json_encode($array) to convert index arrays or associative arrays; 2. If Chinese characters are included, add the JSON_UNESCAPED_UNICODE parameter to retain the original characters; 3. Use JSON_PRETTY_PRINT to beautify the output format during debugging; 4. When outputting JSON, header('Content-Type:application/json'); 5. JSON can be written to the file through file_put_contents; this function automatically processes boolean values, numbers, and strings
- PHP Tutorial . Backend Development 701 2025-07-04 01:56:51
-
- how to remove null or empty values from a php array
- To clean up null or null values ??in PHP arrays, you can use the array_filter function, which will remove all false values ??such as null, empty strings, false, 0 and empty arrays by default. If you want to remove only null and empty strings, you need to customize the filtering conditions to retain other false values; use array_values ??to re-index the array key names; recursive filtering is required when dealing with multi-dimensional arrays; pay attention to spaces, data types and performance issues. 1. Use array_filter to filter false values ??by default; 2. Custom callbacks retain specific values; 3. Array_values ??reset key names; 4. Recursive functions handle multi-dimensional arrays; 5. Pay attention to the impact of spaces, types and performance.
- PHP Tutorial . Backend Development 916 2025-07-04 01:56:12
-
- php string to date
- To convert a string to date format, use PHP's strtotime() or DateTime::createFromFormat() method. 1. Use strtotime() to be suitable for common standard formats. After returning the timestamp, the target format is output with date(); 2. Recommend DateTime::createFromFormat() for non-standard formats. The input format must be clearly specified to ensure accurate parsing; 3. Note that the input format must be strictly matched, the time zone settings must be processed, and the return value is false to avoid errors.
- PHP Tutorial . Backend Development 760 2025-07-04 01:52:40
-
- How to return an array from a PHP function?
- There are three ways to return an array from a function in PHP: one is to directly return a static array, which is suitable for situations where the data volume is small and the structure is fixed, such as return['red','green','blue']; the second is to dynamically generate an array, build an array through loop or conditional judgment, such as extracting data from the simulated database results and returning; the third is to simplify the processing of existing array logic in combination with built-in functions such as array_map, such as returning a square array of numbers. Notes include: the default return of the value of the array rather than a reference, avoiding returning null but returning an empty array, and PHP7 recommends using type declarations to improve code security and maintainability.
- PHP Tutorial . Backend Development 763 2025-07-04 01:51:01
-
- what is the difference between php array_push and just adding an element
- There are two ways to add elements to an array in PHP: 1. The array_push() function can add multiple elements at once and return a new length, but variables need to be passed and the performance is slightly poor; 2. The addition of empty square brackets [] directly is simpler and more efficient, suitable for single elements and frequent operations. The order of the two is consistent, and it is recommended to use the [] operator first.
- PHP Tutorial . Backend Development 826 2025-07-04 01:49:31
-
- php check if date is valid
- There are three main methods for verifying the validity of dates in PHP: 1. Use the checkdate function to verify the Gregorian date, which is suitable for the standard MM/DD/YYYY format, which can judge leap years but does not support non-Gregorian calendars; 2. Use DateTime::createFromFormat to verify specific formats such as 'YYY-MM-DD', 'd/m/Y', etc., which are more flexible and can be used in combination with time verification; 3. Make loose judgments on timestamps or fuzzy formats through strtotime, but are not suitable for strict verification. Select the appropriate method according to the scene: select checkdate for the simple date, use DateTime::createFromFormat for complex formats, and use strt for temporary judgment
- PHP Tutorial . Backend Development 963 2025-07-04 01:46:51
-
- php get start of year
- Getting the start of a year in PHP can be achieved through the strtotime function or the DateTime class. The way to use strtotime is: $firstDayOfYear=strtotime('2024-01-01'); or dynamically get the current year: $year=date('Y'); $firstDayOfYear=strtotime("$year-01-01"); You can also use DateTime object-oriented method: $date=newDateTime('2024-01-01'); or $date=newDateTime('first
- PHP Tutorial . Backend Development 806 2025-07-04 01:32:21
-
- how to access a multidimensional php array
- ToaccesselementsinamultidimensionalPHParray,usemultiplesetsofsquarebracketstonavigatethrougheachlevelofthestructure.1.Understandthearray’sstructure—multidimensionalarrayscontainotherarrays,eithernumericallyindexed,associative,orboth.2.Accesselementsb
- PHP Tutorial . Backend Development 347 2025-07-04 01:14:51
-
- How to get a list of all built-in PHP functions?
- There are three main ways to get all built-in PHP functions: 1. Check the "FunctionReference" section in the official document (php.net) to get the most authoritative and detailed function list and description; 2. Use the get_defined_functions() function in the code and access its 'internal' key to dynamically obtain all built-in function names in the current environment; 3. Run PHP scripts through the command line, use php-r to execute relevant commands and save the results to a file, which is suitable for automated processing and debugging environments.
- PHP Tutorial . Backend Development 837 2025-07-04 01:06:30
-
- Is it possible for a PHP function to have optional parameters?
- Yes,PHPfunctionscanhaveoptionalparametersbyassigningdefaultvaluesinthefunctiondefinition.Toimplementthis,assignadefaultvaluetoaparameter,suchasfunctiongreet($name="Guest"),whichuses"Guest"ifnoargumentisprovided.1.Optionalparameter
- PHP Tutorial . Backend Development 230 2025-07-04 00:58:31
-
- php get end of week
- To obtain the end time of this week in PHP, you need to select the corresponding method according to the starting date of the week. If Sunday is the ending day, you can use strtotime('sundaythisweek') to get the timestamp and format the output; if Saturday is the ending day, you can use strtotime('saturdaythisweek'); for more flexible needs, you can use the DateTime class to match the setISODate method to set the seventh day (Sunday) as the ending day; in actual applications, you need to pay attention to the time zone setting, cross-month and New Year situation, and adjust and verify the current week value.
- PHP Tutorial . Backend Development 699 2025-07-04 00:57:31
-
- php get end of year
- To get the available spliced ??date string or DateTime class on the last day of a certain year, you need to pay attention to the time zone and dynamic year. 1. Directly splicing such as $year.'-12-31' can get the string date; 2. Use strtotime() or newDateTime() to convert timestamps or objects to more flexible processing; 3. Cross-time zone applications should manually specify the time zone to avoid errors; 4. Dynamic years can be automatically obtained by date('Y') or 'December31thisyear'.
- PHP Tutorial . Backend Development 258 2025-07-04 00:56:51
Tool Recommendations
jQuery enterprise message form contact code
jQuery enterprise message form contact code is a simple and practical enterprise message form and contact us introduction page code.
form button
2024-02-29
HTML5 MP3 music box playback effects
HTML5 MP3 music box playback special effect is an mp3 music player based on HTML5 css3 to create cute music box emoticons and click the switch button.
Player special effects
2024-02-29
HTML5 cool particle animation navigation menu special effects
HTML5 cool particle animation navigation menu special effect is a special effect that changes color when the navigation menu is hovered by the mouse.
Menu navigation
2024-02-29
jQuery visual form drag and drop editing code
jQuery visual form drag and drop editing code is a visual form based on jQuery and bootstrap framework.
form button
2024-02-29
Organic fruit and vegetable supplier web template Bootstrap5
An organic fruit and vegetable supplier web template-Bootstrap5
Bootstrap template
2023-02-03
Bootstrap3 multifunctional data information background management responsive web page template-Novus
Bootstrap3 multifunctional data information background management responsive web page template-Novus
backend template
2023-02-02
Real estate resource service platform web page template Bootstrap5
Real estate resource service platform web page template Bootstrap5
Bootstrap template
2023-02-02
Simple resume information web template Bootstrap4
Simple resume information web template Bootstrap4
Bootstrap template
2023-02-02
Cute summer elements vector material (EPS PNG)
This is a cute summer element vector material, including the sun, sun hat, coconut tree, bikini, airplane, watermelon, ice cream, ice cream, cold drink, swimming ring, flip-flops, pineapple, conch, shell, starfish, crab, Lemons, sunscreen, sunglasses, etc., the materials are provided in EPS and PNG formats, including JPG previews.
PNG material
2024-05-09
Four red 2023 graduation badges vector material (AI EPS PNG)
This is a red 2023 graduation badge vector material, four in total, available in AI, EPS and PNG formats, including JPG preview.
PNG material
2024-02-29
Singing bird and cart filled with flowers design spring banner vector material (AI EPS)
This is a spring banner vector material designed with singing birds and a cart full of flowers. It is available in AI and EPS formats, including JPG preview.
banner picture
2024-02-29
Golden graduation cap vector material (EPS PNG)
This is a golden graduation cap vector material, available in EPS and PNG formats, including JPG preview.
PNG material
2024-02-27
Home Decor Cleaning and Repair Service Company Website Template
Home Decoration Cleaning and Maintenance Service Company Website Template is a website template download suitable for promotional websites that provide home decoration, cleaning, maintenance and other service organizations. Tip: This template calls the Google font library, and the page may open slowly.
Front-end template
2024-05-09
Fresh color personal resume guide page template
Fresh color matching personal job application resume guide page template is a personal job search resume work display guide page web template download suitable for fresh color matching style. Tip: This template calls the Google font library, and the page may open slowly.
Front-end template
2024-02-29
Designer Creative Job Resume Web Template
Designer Creative Job Resume Web Template is a downloadable web template for personal job resume display suitable for various designer positions. Tip: This template calls the Google font library, and the page may open slowly.
Front-end template
2024-02-28
Modern engineering construction company website template
The modern engineering and construction company website template is a downloadable website template suitable for promotion of the engineering and construction service industry. Tip: This template calls the Google font library, and the page may open slowly.
Front-end template
2024-02-28
