Easy Random Number
Author
Ok, I have only been programming for around a month now. I made my first program but I have one thing to finish it off fully. I need txtOrderNo.Text to feature a unique random number on entering the form. If possible, I would like an easy guide how to this. I have searched on the site but I can''t get it to work. Thanks.
well this is what i use for my random numbers
//random.h#pragma once#include<time.h>#include<stdlib.h>#define RANDOMIZE srand((unsigned)time(0));template <class type>type __forceinline __fastcall Random(type min,type max){ return( (rand() % int((max - min + 1)) ) + min);}
If I recall correctly, Rnd() or Rand() or Random() will generate a random number between 0 and 64000. If you want a random number between 0 and 100, write An_Int_Variable = Rnd()%101
quote:Original post by Martyn
Ok, I have only been programming for around a month now. I made my first program but I have one thing to finish it off fully. I need txtOrderNo.Text to feature a unique random number on entering the form. If possible, I would like an easy guide how to this. I have searched on the site but I can't get it to work. Thanks.
You can use the CoCreateGUID() function in the API. I used it while attempting to write a Gnutella client (each Gnutella Packet requires it own unique ID).
Here is some example code:
Option ExplicitDeclare Function CoCreateGuid Lib "OLE32.DLL" (pGuid As GUID) As LongType GUID Data1 As Long Data2 As Integer Data3 As Integer Data4(7) As ByteEnd Type Function GetGUID() As String Dim lResult As Long Dim lguid As GUID Dim MyguidString As String Dim MyGuidString1 As String Dim MyGuidString2 As String Dim MyGuidString3 As String Dim DataLen As Integer Dim StringLen As Integer Dim i% Dim cnt As Integer Dim dt As String Dim tmp As String Const S_OK = 0 tmp = "" On Error GoTo error_olemsg lResult = CoCreateGuid(lguid) If lResult = S_OK Then MyGuidString1 = Hex$(lguid.Data1) StringLen = Len(MyGuidString1) DataLen = Len(lguid.Data1) MyGuidString1 = LeadingZeros(2 * DataLen, StringLen) _ & MyGuidString1 'First 4 bytes (8 hex digits) MyGuidString2 = Hex$(lguid.Data2) StringLen = Len(MyGuidString2) DataLen = Len(lguid.Data2) MyGuidString2 = LeadingZeros(2 * DataLen, StringLen) _ & Trim$(MyGuidString2) 'Next 2 bytes (4 hex digits) MyGuidString3 = Hex$(lguid.Data3) StringLen = Len(MyGuidString3) DataLen = Len(lguid.Data3) MyGuidString3 = LeadingZeros(2 * DataLen, StringLen) _ & Trim$(MyGuidString3) 'Next 2 bytes (4 hex digits) GetGUID = MyGuidString1 & MyGuidString2 & MyGuidString3 Dim sByte As String For i% = 0 To 7 sByte = Hex(lguid.Data4(i%)) If Len(sByte) < 2 Then sByte = "0" & sByte MyguidString = MyguidString & sByte Next i% 'MyGuidString contains last 8 bytes of Guid (16 hex digits) GetGUID = GetGUID & MyguidString Else GetGUID = "00000000" ' return zeros if function unsuccessful End If 'Convert to hex For cnt = 1 To Len(GetGUID) Step 2 dt = Mid(GetGUID, cnt, 2) tmp = tmp & Chr(Val("&h" & dt)) Next cnt GetGUID = tmp Exit Functionerror_olemsg: MsgBox "Error " & Str(Err) & ": " & Error$(Err) GetGUID = "00000000" Exit FunctionEnd FunctionFunction LeadingZeros(ExpectedLen As Integer, ActualLen As Integer) As String LeadingZeros = String$(ExpectedLen - ActualLen, "0")End Functionin this example the output is in hex but that can very easily be changed. I am not too sure about the inner workings of the CoCreateGUID function but I believe it uses the system clock as part of process.
I hope this helps.
[edited by - prh99 on January 18, 2004 6:31:33 PM]
[edited by - prh99 on January 18, 2004 6:35:57 PM]
In VB the Rnd() function will return a random number between 0 and 1. If you want the number to for example be between 1 and 10, use:
[Edit: Formatting was making the page too wide.]
[edited by - Oluseyi on January 18, 2004 7:06:12 PM]
Private Sub Form_Load() Randomize Timer ' This will initiate the random generator, if you don't use this line ' every run of the program will use the same sequence of random numbers txtOrderNo.Text = "" & Int(Rnd() * 10 + 1)End Sub [Edit: Formatting was making the page too wide.]
[edited by - Oluseyi on January 18, 2004 7:06:12 PM]
//random.h#pragma once#include<time.h>#include<stdlib.h>#define RANDOMIZE srand((unsigned)time(0));template <class type>type __forceinline __fastcall Random(type min,type max){ return( (rand() % int((max - min + 1)) ) + min);}//main.cpp#include<random.h>#include<iostream.h>int main(){ RANDOMIZE;//make sure the random numbers are random cout<<Random(0,100)<<endl;//output a random number 0 to 100 cout<<Random(0.0, 2.0)<<endl;//output a random floating point ///value 0.0 - 2.0}/* it just looks comfusing because it is setup to take any kind of data (ints, floats, doubles, longs etc) just call the function like this Random(lowest number desired , highest number desired);*/
vaneger.. what''s wrong with you? Can''t you see he said "VB6"?
Besides, your code sucks. A simple macro would be superior to your code (if it compiled).
Besides, your code sucks. A simple macro would be superior to your code (if it compiled).
Function random(lowest As Double, highest As Double) As Double random = lowest + Rnd * (highest - lowest)End Functioncall random with the first arg as the lowest value that the random number can be, and the seconds arg as the highest value it can be.
[edited by - aftermath on January 18, 2004 8:26:13 PM]
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