Home Backend Development PHP Tutorial 遇到怪事了 PHP 设定了range范围 但运行结果却是显示在范围之外,为什么

遇到怪事了 PHP 设定了range范围 但运行结果却是显示在范围之外,为什么

Jun 13, 2016 pm 12:26 PM
array nbsp range red

碰到怪事了 PHP 设定了range范围 但运行结果却是显示在范围之外,为什么?
一段PHP随机代码,设定了range(1,30)但多次运行结果会显示出0,why?
代码:
$red1=range(1,30);
$sc1=array_rand($red1,8);
?>


foreach($sc1 as $v){
echo "$v ";
}
?>

$red2=range(1,30);
$sc1=array_rand($red2,8);
?>

foreach($sc1 as $v){
echo "$v ";
}
?>
$red1=range(1,30);
$sc1=array_rand($red1,8);
?>

foreach($sc1 as $v){
echo "$v ";
}
?>

$red2=range(1,30);
$sc1=array_rand($red2,8);
?>

foreach($sc1 as $v){
echo "$v ";
}
?>
请多刷新几次,第一个数竟然会出现0?。。为什么?


------解决思路----------------------

------解决思路----------------------
你想要的应该是打乱数组排序,取8个元素出来是吧?

shuffle($red1);
$red1 = array_splice($red1,0,8);
------解决思路----------------------
array_rand()随机取出来的是键名;
Statement of this Website
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn

Hot AI Tools

Undresser.AI Undress

Undresser.AI Undress

AI-powered app for creating realistic nude photos

AI Clothes Remover

AI Clothes Remover

Online AI tool for removing clothes from photos.

Undress AI Tool

Undress AI Tool

Undress images for free

Clothoff.io

Clothoff.io

AI clothes remover

Video Face Swap

Video Face Swap

Swap faces in any video effortlessly with our completely free AI face swap tool!

Hot Article

Roblox: Bubble Gum Simulator Infinity - How To Get And Use Royal Keys
3 weeks ago By 尊渡假赌尊渡假赌尊渡假赌
Nordhold: Fusion System, Explained
3 weeks ago By 尊渡假赌尊渡假赌尊渡假赌
Mandragora: Whispers Of The Witch Tree - How To Unlock The Grappling Hook
3 weeks ago By 尊渡假赌尊渡假赌尊渡假赌

Hot Tools

Notepad++7.3.1

Notepad++7.3.1

Easy-to-use and free code editor

SublimeText3 Chinese version

SublimeText3 Chinese version

Chinese version, very easy to use

Zend Studio 13.0.1

Zend Studio 13.0.1

Powerful PHP integrated development environment

Dreamweaver CS6

Dreamweaver CS6

Visual web development tools

SublimeText3 Mac version

SublimeText3 Mac version

God-level code editing software (SublimeText3)

Hot Topics

Java Tutorial
1666
14
PHP Tutorial
1273
29
C# Tutorial
1253
24
What steps are required to configure CentOS in HDFS What steps are required to configure CentOS in HDFS Apr 14, 2025 pm 06:42 PM

Building a Hadoop Distributed File System (HDFS) on a CentOS system requires multiple steps. This article provides a brief configuration guide. 1. Prepare to install JDK in the early stage: Install JavaDevelopmentKit (JDK) on all nodes, and the version must be compatible with Hadoop. The installation package can be downloaded from the Oracle official website. Environment variable configuration: Edit /etc/profile file, set Java and Hadoop environment variables, so that the system can find the installation path of JDK and Hadoop. 2. Security configuration: SSH password-free login to generate SSH key: Use the ssh-keygen command on each node

How to configure slow query log in centos redis How to configure slow query log in centos redis Apr 14, 2025 pm 04:54 PM

Enable Redis slow query logs on CentOS system to improve performance diagnostic efficiency. The following steps will guide you through the configuration: Step 1: Locate and edit the Redis configuration file First, find the Redis configuration file, usually located in /etc/redis/redis.conf. Open the configuration file with the following command: sudovi/etc/redis/redis.conf Step 2: Adjust the slow query log parameters in the configuration file, find and modify the following parameters: #slow query threshold (ms)slowlog-log-slower-than10000#Maximum number of entries for slow query log slowlog-max-len

How to use the Redis cache solution to efficiently realize the requirements of product ranking list? How to use the Redis cache solution to efficiently realize the requirements of product ranking list? Apr 19, 2025 pm 11:36 PM

How does the Redis caching solution realize the requirements of product ranking list? During the development process, we often need to deal with the requirements of rankings, such as displaying a...

Using Dicr/Yii2-Google to integrate Google API in YII2 Using Dicr/Yii2-Google to integrate Google API in YII2 Apr 18, 2025 am 11:54 AM

VprocesserazrabotkiveB-enclosed, Мнепришлостольностьсясзадачейтерациигооглапидляпапакробоглесхетсigootrive. LEAVALLYSUMBALLANCEFRIABLANCEFAUMDOPTOMATIFICATION, ČtookazaLovnetakProsto, Kakaožidal.Posenesko

What should I do if the Redis cache of OAuth2Authorization object fails in Spring Boot? What should I do if the Redis cache of OAuth2Authorization object fails in Spring Boot? Apr 19, 2025 pm 08:03 PM

In SpringBoot, use Redis to cache OAuth2Authorization object. In SpringBoot application, use SpringSecurityOAuth2AuthorizationServer...

What files do you need to modify in HDFS configuration CentOS? What files do you need to modify in HDFS configuration CentOS? Apr 14, 2025 pm 07:27 PM

When configuring Hadoop Distributed File System (HDFS) on CentOS, the following key configuration files need to be modified: core-site.xml: fs.defaultFS: Specifies the default file system address of HDFS, such as hdfs://localhost:9000. hadoop.tmp.dir: Specifies the storage directory for Hadoop temporary files. hadoop.proxyuser.root.hosts and hadoop.proxyuser.ro

How to solve the error in CentOS HDFS configuration How to solve the error in CentOS HDFS configuration Apr 14, 2025 pm 07:06 PM

Troubleshooting HDFS configuration errors under CentOS Systems This article is intended to help you solve problems encountered when configuring HDFS in CentOS systems. Please follow the following steps to troubleshoot: Java environment verification: Confirm that the JAVA_HOME environment variable is set correctly. Add the following in the /etc/profile or ~/.bashrc file: exportJAVA_HOME=/path/to/your/javaexportPATH=$JAVA_HOME/bin: $PATHExecute source/etc/profile or source~/.bashrc to make the configuration take effect. Hadoop

How to choose a GitLab database in CentOS How to choose a GitLab database in CentOS Apr 14, 2025 pm 05:39 PM

When installing and configuring GitLab on a CentOS system, the choice of database is crucial. GitLab is compatible with multiple databases, but PostgreSQL and MySQL (or MariaDB) are most commonly used. This article analyzes database selection factors and provides detailed installation and configuration steps. Database Selection Guide When choosing a database, you need to consider the following factors: PostgreSQL: GitLab's default database is powerful, has high scalability, supports complex queries and transaction processing, and is suitable for large application scenarios. MySQL/MariaDB: a popular relational database widely used in Web applications, with stable and reliable performance. MongoDB:NoSQL database, specializes in

See all articles