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Randomly generating number

Hi, in my application, when a user clicks the add button, the text fileds are activated for the user to input client information, like client ID, name, address etc. The application also connects to a database. What i need to do is randomly generate a three digit clientID, and populate it to the client id textbox when the add button is pressed, but i also need to make sure that the ID generated should not already exist in the database... any ideas...

intox1221

ASKER

Also im using .NET environment...

frodoman

intox1221,

This is going to require generating a random number, then searching the database for it. If it's found, you'll have to repeat the process. The more users you get the more times you'll have to repeat this process.

I can help if you're certain this is what you want to do, but I'd take a different approach if possible. Instead of a random number, why not just SELECT MAX(userid) +1 to increment the userid by 1 each time?

Frodoman

frodoman

If you do go w/ the random approach, here's the random number code:

MyInteger = CInt(Int(1000*Rnd()))

intox1221

ASKER

i declared myinteger as int32 and then equated it with txtClient.text but the application pukes it...
something im missing ?

frodoman

Did you use tostring?

txtClient.text = YourInt32.ToString

intox1221

ASKER

i did..

MyInteger = Cint (txtclient.text)

Also i need to have option strict on which disallows implicit conversions.

frodoman

I assume it's a type conversion problem? What is displayed in txtClient before the error? What error is shown?

You might have extra spaces so also try MyInteger = CType(trim(txtclient.text),Int32)

intox1221

ASKER

Still pukin it... this is what i got....

Dim myinteger As Int32

myinteger = CInt(Int(1000 * Rnd()))

myinteger = CType(Trim(txtClient.Text), Int32)

frodoman

Where is the error and what is the description of the error?

intox1221

ASKER

thats the error message.

An unhandled exception of type 'System.InvalidCastException' occurred in microsoft.visualbasic.dll

Additional information: Cast from string "" to type 'Integer' is not valid.

frodoman

This means that txtClient is empty when you reach the code:

myinteger = CType(Trim(txtClient.Text), Int32)

The block below will avoid the error and use a '0' if the textbox is empty, but you should probably examine your code for why it is empty.

If IsNumeric(txtClient.Text) Then
myinteger = CType(Trim(txtClient.Text), Int32)
Else
myinteger = 0
End If

What exactly are you trying to accomplish with this code? Seems like you create the random number and you'd want to put it INTO your textbox instead of pulling something OUT of it...

Dim myinteger As Int32
myinteger = CInt(Int(1000 * Rnd()))
txtClient.Text = CType(myinteger,String)

intox1221

ASKER

thats exactly what i want. My textbox is empty when the add button is pressed and i want fill it with the randomly generated code... what the add button does is it activates the textfileds, as they are read only or deactivated before that. Then upon pressing the save button, is when i want the data should be sent to the database (that i have already done). So all i wanna do is populate the text field with the randomly generated code.

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frodoman

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intox1221

ASKER

Sweeeeet. Works like a charm. But it also generates numbers like 54, 14... can i make it atleast 3 digits... or 014 instead of 14... ??????

intox1221

ASKER

actually that doesnt make much of a difference. nevermind that...

intox1221

ASKER

thanks for ur help on this one. I have another question to the follow up of my current question. So i am posting it as a new question, thanks for ur help. The topic should be "Randomly generating number take 2"