<% '******************************************************* '* ASP 101 Sample Code - http://www.asp101.com/ * '* * '* This code is made available as a service to our * '* visitors and is provided strictly for the * '* purpose of illustration. * '* * '* http://www.asp101.com/samples/license.asp * '* * '* Please direct all inquiries to webmaster@asp101.com * '******************************************************* %> <% Dim intLowerBound ' Lower bound of the random number range Dim intUpperBound ' Upper bound of the random number range Dim intRangeSize ' Size of the range Dim sngRandomValue ' A random value from 0 to intRangeSize Dim intRandomInteger ' Our final result - random integer to return ' Retrieve lower and upper bound requests if they're there ' o/w set to defaults of 0 and 100 If IsNumeric(Request.QueryString("lowerbound")) Then intLowerBound = CLng(Request.QueryString("lowerbound")) Else intLowerBound = 0 End If If IsNumeric(Request.QueryString("upperbound")) Then intUpperBound = CLng(Request.QueryString("upperbound")) ' Add a line to deal with default case of 0 to 0. ' This really isn't neccessary, but I do it so the ' sample doesn't default to generating a number between ' 0 and 0 and always return 0 when no bounds are provided. If intLowerBound = 0 And intUpperBound = 0 Then intUpperBound = 100 Else intUpperBound = 100 End If ' Check for people asking for a number from in an inappropriate ' range (ie: 50 to 10) and swap the bounds If intLowerBound > intUpperBound Then ' I really should've declared a temporary variable for this ' swapping, but I was lazy and this one was already defined ' and I don't use it till later... oh all right I'll do it ' the "right" way... actually even this is bad... I should've ' defined this up top... so sue me... hey it's free code what ' do you want from me? Dim iTemp iTemp = intLowerBound intLowerBound = intUpperBound intUpperBound = iTemp End If ' Initialize the random number generator. ' Randomize can actually take parameters telling it how to initialize ' things, but for the most you'll just want to call it without passing ' it anything. Randomize() ' Generate our random number. ' The Rnd function does most of the work. It returns a value in the ' range 0 <= value < 1 so to generate a random integer in the specified ' range we need to do some calculation. Specifically we take the size ' of the range in which we want to generate the number (add 1 so the ' upper bound can be generated!) and then multiply it by our random ' element. Then to place the value into the correct range of numbers ' we add the lower bound. Finally we truncate the number leaving us ' with the integer portion which is always somewhere between the ' lower bound and upper bound (inclusively). ' Find range size intRangeSize = intUpperBound - intLowerBound + 1 ' Get a random number from 0 to the size of the range sngRandomValue = intRangeSize * Rnd() ' Center the range of possible random numbers over the desired result set sngRandomValue = sngRandomValue + intLowerBound ' Convert our value to an integer intRandomInteger = Int(sngRandomValue) ' The above 4 lines are equivilent to the popular shorter version ' below. I split it up so I could indicate what each step is doing. ' intRandomInteger = Int((intUpperBound - intLowerBound + 1) * Rnd + intLowerBound) ' Show out output indicating what we've done and our result. %> You asked for a random number between <%= intLowerBound %> and <%= intUpperBound %>.
The computer returned: <%= intRandomInteger %>
Generate a random number between and