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Anurag Sharma
Anurag Sharma

Total Post:40

Posted on    October-20-2010 7:49 AM

 VB.Net VB.Net 

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Hello Guys,
I am very new in VB.NET and I have a small task to generate random numbers in VB.NET.
Please provide me sample of code.

Uttam Misra

Total Post:125

Posted on    October-20-2010 8:01 AM

Check this


Dim n as Integer
dim sm as Integer
Redim cntArray(High-Low)
For x as Integer = 0 to Iter
 n =rand.Next(Low,High)
 sm += 1
 cntArray(n-Low) +=1
Dim st1 as string
For x As Integer = 0 to cntArray.Length - 1
 st1 = (x +Low).ToString 'The number.
 st1 &="  " & cntArray(x).ToString'The count of that number.
 st1 &="  " & (100 * cntArray(x) /sm).ToString 'The percent of that number
 <your listboxhere>.Items.Add(st1)

manigovi manigovinth
manigovi manigovinth

Total Post:3

Posted on    August-10-2011 2:20 AM

Hi...i provides sample vb.net codes here...

The following code returns a random number:

Dim num As Integer = random.Next()

The following code returns a random number less than 1000.

Dim num As Integer = random.Next(1000)

The following code returns a random number between min and max:

Private Function RandomNumber(min As Integer, max As Integer) As Integer
   Dim random As New Random()
   Return random.Next(min, max)
End Function 'RandomNumber

At some point, you may also want to generate random strings. I have created a method, which takes first parameter as the size of string and second parameter if you want the string to be lowercase.

'/ '/ Generates a random string with the given length
'/ '/ Size of the string '/ If true, generate lowercase string
'/ Random string
Private Function RandomString(size As Integer, lowerCase As Boolean) As String
   Dim builder As New StringBuilder()
   Dim random As New Random()
   Dim ch As Char
   Dim i As Integer
   For i = 0 To size - 1
      ch = Convert.ToChar(Convert.ToInt32((26 * random.NextDouble() + 65)))
If lowerCase Then
      Return builder.ToString().ToLower()
   End If
   Return builder.ToString()
End Function 'RandomString

You can even combine the two methods-RandomNumber and RandomString to generate a combination of random string and numbers. For example, the following code generates a password of length 10 with first 4 letters lowercase, next 4 letters numbers, and last 2 letters as uppercase.

Public Function GetPassword() As String
   Dim builder As New StringBuilder()
   builder.Append(RandomInt(1000, 9999))
   Return builder.ToString()
End Function 'GetPassword



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