Random password string generator using number and alphabets

We can generate a set of random digits by combining a set of alphabets and numbers. After this our random string will have a random combination of alphabets and numbers. You can read how to generate random numbers by reading math random generator and how to generate random alphabets here .

We will use these two methods to generate random numbers and random characters. We will add ( or combine ) these two to get our random string. Here to get a combination we will use random methods so the positions of numbers and alphabets are not fixed.

Using this you can generate random password strings for any application ( like login script etc )

O4510105SO6I

Now we will keep the script inside a function and use it when required. Here we will make it flexible by accepting one input to the function by which we will tell how many digits are required. So the length of the random string can be managed based on the script design.

Here is the full function with detail explanation with it ( read the comments )

<?Php
function random_generator($digits){
srand ((double) microtime() * 10000000);
//Array of alphabets
$input = array ("A", "B", "C", "D", "E","F","G","H","I","J","K","L","M","N","O","P","Q",
"R","S","T","U","V","W","X","Y","Z");

$random_generator="";// Initialize the string to store random numbers
for($i=1;$i<$digits+1;$i++){ // Loop the number of times of required digits

if(rand(1,2) == 1){// to decide the digit should be numeric or alphabet
// Add one random alphabet 
$rand_index = array_rand($input);
$random_generator .=$input[$rand_index]; // One char is added

}else{

// Add one numeric digit between 1 and 10
$random_generator .=rand(1,10); // one number is added
} // end of if else

} // end of for loop 


return $random_generator;
} // end of function

echo random_generator(10);
?>

STRING REFERENCE how to change all the letters to upper case

Subhendu Mohapatra

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arman patel	26-05-2009
very comprencive and use full tutorial for me thx.

bright-tutorials.com	31-12-2009
This is another method to do it, but there are others. Good job using mt_rand not many use it!

Php Programmer	10-08-2017
Great!! This tutorial was really helpful to create a random number and alphabets. Simple but effective. Thanks.

Harry	29-07-2009
WOW thanks for this!

ketan	08-03-2010
good code for beginner

sattar	02-10-2012
easy and simple tutor. are available here

String with random number and alphabets

Subhendu Mohapatra