To merge two PHP arrays and keep unique values, there are two main methods. 1. For index arrays or only deduplication, use array_merge and array_unique combinations: first merge array_merge($array1, $array2) and then use array_unique() to deduplicate them to finally get a new array containing all unique values; 2. For associative arrays and want to retain key-value pairs in the first array, use the operator: $result = $array1 $array2, which will ensure that the keys in the first array will not be overwritten by the second array. These two methods are suitable for different scenarios, and are selected based on whether the key names need to be retained or only the uniqueness of the value is focused on.
Sometimes we need to merge two PHP arrays and only retain unique values. This is common when dealing with data deduplication, filtering, or integrating data from multiple sources. In fact, the method is not complicated, just use the right function.
Use array_merge and array_unique to deduplicate
This is the most commonly used method: first merge the array, then remove the heavy. The steps are as follows:
- Use
array_merge($array1, $array2)to combine two arrays into one - Use
array_unique()to remove duplicate values
$array1 = [1, 2, 3]; $array2 = [3, 4, 5]; $result = array_unique(array_merge($array1, $array2));
In this way, $result will be [1, 2, 3, 4, 5] . Note that if there are strings or other types of data in the array, this method also applies. Moreover, it can also handle the situation of index arrays and associative arrays. However, when using array_merge in associative arrays, the subsequent array will be retained if the value of the same key name is the same.
If it is an associative array, consider using Operators
If you have two associative arrays (that is, the kind that uses strings as key names) and want to keep the values ??in the first array and only add the items in the second array that do not exist in the first one, you can write this:
$array1 = ['a' => 1, 'b' => 2]; $array2 = ['b' => 3, 'c' => 4]; $result = $array1 $array2;
The result will be:
['a' => 1, 'b' => 2, 'c' => 4]
As you can see, 'b' => 3 in $array2 is ignored because $array1 already has the 'b' key. This method is suitable for you to only want to keep the key-value pairs already in the first array, while completing the part of the second array that has no conflicts.
For PHP 7.4, can I use the array_union function?
Actually not. PHP does not have a built-in array_union function. But some developers will encapsulate a function similar to the function to simulate this behavior. for example:
function array_union($a, $b) {
return $a $b;
} However, this only applies to associative arrays. For index arrays, it is more safe to recommend the aforementioned array_merge array_unique method.
Basically that's it. When choosing different combination methods in different scenarios, the key depends on whether you want to keep the key names first or only care about the uniqueness of the value.
The above is the detailed content of How to combine two php arrays unique values?. For more information, please follow other related articles on the PHP Chinese website!
Hot AI Tools
Undress AI Tool
Undress images for free
Undresser.AI Undress
AI-powered app for creating realistic nude photos
AI Clothes Remover
Online AI tool for removing clothes from photos.
Clothoff.io
AI clothes remover
Video Face Swap
Swap faces in any video effortlessly with our completely free AI face swap tool!
Hot Article
Hot Tools
Notepad++7.3.1
Easy-to-use and free code editor
SublimeText3 Chinese version
Chinese version, very easy to use
Zend Studio 13.0.1
Powerful PHP integrated development environment
Dreamweaver CS6
Visual web development tools
SublimeText3 Mac version
God-level code editing software (SublimeText3)
Hot Topics
How to use PHP to build social sharing functions PHP sharing interface integration practice
Jul 25, 2025 pm 08:51 PM
The core method of building social sharing functions in PHP is to dynamically generate sharing links that meet the requirements of each platform. 1. First get the current page or specified URL and article information; 2. Use urlencode to encode the parameters; 3. Splice and generate sharing links according to the protocols of each platform; 4. Display links on the front end for users to click and share; 5. Dynamically generate OG tags on the page to optimize sharing content display; 6. Be sure to escape user input to prevent XSS attacks. This method does not require complex authentication, has low maintenance costs, and is suitable for most content sharing needs.
How to use PHP combined with AI to achieve text error correction PHP syntax detection and optimization
Jul 25, 2025 pm 08:57 PM
To realize text error correction and syntax optimization with AI, you need to follow the following steps: 1. Select a suitable AI model or API, such as Baidu, Tencent API or open source NLP library; 2. Call the API through PHP's curl or Guzzle and process the return results; 3. Display error correction information in the application and allow users to choose whether to adopt it; 4. Use php-l and PHP_CodeSniffer for syntax detection and code optimization; 5. Continuously collect feedback and update the model or rules to improve the effect. When choosing AIAPI, focus on evaluating accuracy, response speed, price and support for PHP. Code optimization should follow PSR specifications, use cache reasonably, avoid circular queries, review code regularly, and use X
PHP creates a blog comment system to monetize PHP comment review and anti-brush strategy
Jul 25, 2025 pm 08:27 PM
1. Maximizing the commercial value of the comment system requires combining native advertising precise delivery, user paid value-added services (such as uploading pictures, top-up comments), influence incentive mechanism based on comment quality, and compliance anonymous data insight monetization; 2. The audit strategy should adopt a combination of pre-audit dynamic keyword filtering and user reporting mechanisms, supplemented by comment quality rating to achieve content hierarchical exposure; 3. Anti-brushing requires the construction of multi-layer defense: reCAPTCHAv3 sensorless verification, Honeypot honeypot field recognition robot, IP and timestamp frequency limit prevents watering, and content pattern recognition marks suspicious comments, and continuously iterate to deal with attacks.
PHP calls AI intelligent voice assistant PHP voice interaction system construction
Jul 25, 2025 pm 08:45 PM
User voice input is captured and sent to the PHP backend through the MediaRecorder API of the front-end JavaScript; 2. PHP saves the audio as a temporary file and calls STTAPI (such as Google or Baidu voice recognition) to convert it into text; 3. PHP sends the text to an AI service (such as OpenAIGPT) to obtain intelligent reply; 4. PHP then calls TTSAPI (such as Baidu or Google voice synthesis) to convert the reply to a voice file; 5. PHP streams the voice file back to the front-end to play, completing interaction. The entire process is dominated by PHP to ensure seamless connection between all links.
How to use PHP to combine AI to generate image. PHP automatically generates art works
Jul 25, 2025 pm 07:21 PM
PHP does not directly perform AI image processing, but integrates through APIs, because it is good at web development rather than computing-intensive tasks. API integration can achieve professional division of labor, reduce costs, and improve efficiency; 2. Integrating key technologies include using Guzzle or cURL to send HTTP requests, JSON data encoding and decoding, API key security authentication, asynchronous queue processing time-consuming tasks, robust error handling and retry mechanism, image storage and display; 3. Common challenges include API cost out of control, uncontrollable generation results, poor user experience, security risks and difficult data management. The response strategies are setting user quotas and caches, providing propt guidance and multi-picture selection, asynchronous notifications and progress prompts, key environment variable storage and content audit, and cloud storage.
PHP realizes commodity inventory management and monetization PHP inventory synchronization and alarm mechanism
Jul 25, 2025 pm 08:30 PM
PHP ensures inventory deduction atomicity through database transactions and FORUPDATE row locks to prevent high concurrent overselling; 2. Multi-platform inventory consistency depends on centralized management and event-driven synchronization, combining API/Webhook notifications and message queues to ensure reliable data transmission; 3. The alarm mechanism should set low inventory, zero/negative inventory, unsalable sales, replenishment cycles and abnormal fluctuations strategies in different scenarios, and select DingTalk, SMS or Email Responsible Persons according to the urgency, and the alarm information must be complete and clear to achieve business adaptation and rapid response.
Beyond the LAMP Stack: PHP's Role in Modern Enterprise Architecture
Jul 27, 2025 am 04:31 AM
PHPisstillrelevantinmodernenterpriseenvironments.1.ModernPHP(7.xand8.x)offersperformancegains,stricttyping,JITcompilation,andmodernsyntax,makingitsuitableforlarge-scaleapplications.2.PHPintegrateseffectivelyinhybridarchitectures,servingasanAPIgateway
PHP integrated AI speech recognition and translator PHP meeting record automatic generation solution
Jul 25, 2025 pm 07:06 PM
Select the appropriate AI voice recognition service and integrate PHPSDK; 2. Use PHP to call ffmpeg to convert recordings into API-required formats (such as wav); 3. Upload files to cloud storage and call API asynchronous recognition; 4. Analyze JSON results and organize text using NLP technology; 5. Generate Word or Markdown documents to complete the automation of meeting records. The entire process needs to ensure data encryption, access control and compliance to ensure privacy and security.
