This function returns an array of unique random numbers. It works just like PHP's rand() with an extra argument for the count of the returned array.
**Update: Added error checking and an optional 4th argument to set the length of the returned numbers.
By : tr4nc3
<?php
# Multiple Unique Random Numbers
#
# array mrand ( int min, int max, int count [, int strlen ] )
function mrand($l,$h,$t,$len=false){
if($l>$h){$a=$l;$b=$h;$h=$a;$l=$b;}
if( (($h-$l)+1)<$t || $t<=0 )return false;
$n = array();
if($len>0){
if(strlen($h)<$len && strlen($l)<$len)return false;
if(strlen($h-1)<$len && strlen($l-1)<$len && $t>1)return false;
do{
$x = rand($l,$h);
if(!in_array($x,$n) && strlen($x) == $len)$n[] = $x;
}while(count($n)<$t);
}else{
do{
$x = rand($l,$h);
if(!in_array($x,$n))$n[] = $x;
}while(count($n)<$t);
}
return $n;
}
## Samples ##
if(!$numbers = mrand(1000,9999,10,4))die("error");
// 20 random, all 7 chars in length
# $numbers = mrand(0,9999999,20,7);
// 20 random, length doesn't matter
# $numbers = mrand(0,9999999,20);
# $numbers = mrand(8000,10000,1,5) // ok
# $numbers = mrand(8000,10000,2,5) // error
# $numbers = mrand(120,100,20); // ok
# $numbers = mrand(100,120,21); // ok
# $numbers = mrand(120,100,21); // ok
# $numbers = mrand(120,100,22); // error
# $numbers = mrand(100,120,22); // error
# $numbers = mrand(120,120,1); // ok
# $numbers = mrand(120,120,2); // error
# $numbers = mrand(120,120,0); // error
# $numbers = mrand(1000000,9999999,3000);
// Sort the array
# sort($numbers);
// Display the array
echo '<pre>';
print_r($number);
echo '</pre>';
?>
| DISCLAIMER: The content provided in this article is not warranted or guaranteed by Developer Shed, Inc. The content provided is intended for entertainment and/or educational purposes in order to introduce to the reader key ideas, concepts, and/or product reviews. As such it is incumbent upon the reader to employ real-world tactics for security and implementation of best practices. We are not liable for any negative consequences that may result from implementing any information covered in our articles or tutorials. If this is a hardware review, it is not recommended to open and/or modify your hardware. |
More Miscellaneous Code Articles
More By Codewalkers
 developerWorks - FREE Tools!
|
David Barnes, Lead Evangelist for IBM Emerging Internet Technologies will discuss aspects of Web 2.0 that bring value to corporations, academia, and government. He'll also discuss IBM's vision around Web 2.0, including the importance of remixability and consumability. The discussion will culminate with examples of various IBM Software Group solutions you can use to get ahead of the Web 2.0 adoption curve.
FREE! Go There Now!
|
|
|
|
As businesses grow increasingly dependent upon Web applications to provide services to customers, employees and partners, these complex applications become more difficult to secure. Although traditional security solutions protect Internet infrastructure layers, they do not guard against HTTP and HTML attacks. Many organizations that conduct security testing still deploy applications that allow attackers to manipulate their logic and wreak havoc on their business. To mitigate this risk, development and delivery teams must address Web application security throughout the lifecycle, addressing the many layers detailed in this paper.
FREE! Go There Now!
|
|
|
|
You probably have thousands of lines of COBOL code loaded with business intelligence and being used to run your business, along with an army of developers maintaining these applications. Learn how to prepare your applications and developers so you can keep that competitive edge and move to a service-oriented architecture with the IBM Rational Enterprise Modernization solutions. Replay is available for 9 months.
FREE! Go There Now!
|
|
|
|
Build secure Web services with transport-level security using IBM Rational Application Developer V7 and IBM WebSphere Application Server V6.1. Follow this three-part series for step-by-step instructions about how to develop Web services and clients, configure HTTP basic authentication, and configure HTTP over SSL (HTTPS). This first part of the series walks you through building a Web service for a simple calculator application. You generate and test two different types of Web services clients: a Java Platform, Enterprise Edition (Java EE) client and a stand-alone Java client. You also handle user-defined exceptions in Web services.
FREE! Go There Now!
|
|
|
|
Join us for this on demand webcast to learn about developing complex systems more quickly and efficiently. We'll cover market drivers for developing, governing and reusing systems software assets and how you can develop system software assets with Rational Asset Manager.
FREE! Go There Now!
|
|
|
|
Join this webcast to see how IBM Data Studio Developer and pureQuery can take the pain out of Java data access. uApplications developed using both Java and SQL have become a common requirement. Database connectivity using Java Database Connectivity (JDBC) to create an application is a multi-step tedious process, and tooling that covers both SQL and Java has been unavailable, until now. IBM Data Studio introduces the pureQuery platform: a high-performance, Java data access platform focused on simplifying the tasks of developing, managing, and optimizing database applications and services.
FREE! Go There Now!
|
|
|
|
Listen to this webcast to get an overview of Info 2.0 and a technical demo of how to quickly build an enterprise mashup. IBM's Info 2.0 technology leverages emerging Web 2.0 technologies such as mashups, feeds, AJAX, and JSON in order to simplify assembly of information using feeds and services. Come learn about the technical elements of Info 2.0 including the Feed Generation framework, Mashup Engine, and mashup assembly components. Learn how to pull information from databases, departmental information, and the Web to create mashups critical to your company’s success. We will also discuss best practices to help you get started.
FREE! Go There Now!
|
|
|
|
Get a free trial download of the latest version of IBM Rational Performance Tester V7.0.1, a load and performance testing solution for teams concerned about the scalability of their Web-based applications. Combining multiple ease-of-use features with granular detail, Rational Performance Tester simplifies the test-creation, load-generation and data-collection processes that help teams ensure the ability of their applications to accommodate required user loads.
FREE! Go There Now!
|
|
|
|
In this webcast, you'll get an introduction to the eXtreme Transaction Processing (XTP) features of WebSphere Extended Deployment and the common architectural traits required by XTP applications. See how WebSphere Extended Deployment's ObjectGrid feature provides a state-of-the-art infrastructure for hosting XTP applications.
FREE! Go There Now!
|
|
|
|
With IBM Rational Systems Development Solution, you can deliver products faster with higher quality. Within this kit, Read the “Model Driven Systems Development” white paper to see how to improve product quality and communication. Then check out the rest of the e-Kit to learn more about important topics that can affect the success of any software project through customer examples, tutorials, informative Webcasts, and best practices for designing, building and managing systems. From start to finish, at every stage in your projects, Rational Systems Development Solution can help your company reach its full potential.
FREE! Go There Now!
|
|
|
|
All FREE IBM® developerWorks Tools!
|
/ 4 
