Generating A Globally Unique ID Of 16 Char String?
Jun 18, 2009
I need to generate a globally unique ID of fixed 16-lengthThe GUID is too long for my purpose. So I wonder is there any way to convert it to a 16-length?If this is not possible, I have a program key of 8 chars, and is thinking of using the DateTime as my key.
I'm creating a program, and as part of it I'm storing a customer ID, which will be automatically generated using some form of combination of the customer's first name and surname? My thought so far has been to declare individual characters as Char and then put them together to automatically generate a customer ID? Problem being
I don't know if I can do this here...but here goes. I want to generate a unique ID of fixed length The trouble is, the code example I found on the web is in C# (or C maybe) which I know nothing about. I tried a web-based C# to VB.net converter but the result doesn't work so its hard to understand what's going on (especially since I have not worked with bytes either this makes it more difficult).
creating unique IDs for each row in a table, to avoid duplicates when inserting the data to a server. The table looks like this:
+--------------+----------+------+-------------+ | brikkenummer | tid | post | anvendt_tid | +--------------+----------+------+-------------+ | 3086360 | 09:43:02 | 98 | 09:43:02 |
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"Brikkenummer" is the number of a device that each person carries with him/her, and "tid" is the time the runner has passed a specific post. The post he/her has passed is described in the column "post".Out of these three columns, is it possible to generate some kind of unique ID? The ID that is generated have to be the same if a row is displayed twice or more, to avoid duplicate entries.
I'm looking for a method of generating unique identifiers for a record class being created locally and then persisted in various formats (XML, SQL, etc.) I've seen people using DateTime and GetHashCode, but that seems to lend itself to duplicate identifiers depending upon the sample size. GUID is a bit overkill, as I don't need anything that unique (large) at the global level. I'm also aware of using GUIDs and GetHashCode to get the size down a bit, but duplicates tend to crop up here as well. Any best practice or method for generating simple unique identifiers?
i want to read a character 1 by 1 from a string and a .txt, i know all about stream reader so for the .txt would it be somthing like:textbox1.text = tr.readCharacter.i would prefer to be able to read from a textbox or String array though.
I need validation for string to comply with next: no space char starts with one delimiter char ends with one delimiter char has no other char as delimiter char. Updated sorry missed that should only be one delimiter char at start and at the end
generating unique ids for invoices,customerids and employee ids, etc. and thought it would be great to share this as i will use it within my aps all the time now.[code]
I am using VB .Net to access the eBay API and store all completed orders in a database. This database is then fed into a proprietary shipping system, which can not handle an order number larger than 20 characters. eBay returns an order number like so 230407279314-680141236013 which is too long. The order number is always 12 numbers a hyphen and 12 more numbers. What I need to do, is turn this (the result can be alpha numerical) into a shorter, unique order key to store in my database alongside the true orderId (so that this can be referenced by the shipping software instead of the actual order number). The reason for the 20 character limit is the barcode algorithm used. Is there any way to achieve this in VB .Net 2010? This number can be anything unique, so long as it does not exist already (even a good uniqueid function would work, but I would have to query the database to make sure it isn't taken)
I am trying to the copy the value from string to char array using String.CopyTo() method.
Here's my code
Dim strString As String = "Hello World!" Dim strCopy(12) As Char strString.CopyTo(0, strCopy, 0, 12)
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Edit : I get the this error at runtime.ArgumentOutOfRangeException Index and count must refer to a location within the string. Parameter name: sourceIndex
What I need is to be able to put in a SortedList a combination of two fields that are non-unique, but the pair is (like database composite keys).More precisly, i have my list, and i want to be able to do this with it
Dim myList = New Generic.SortedList(Of String, String) myList.add("aaa","aaa") myList.add("aaa","bbb")
In my VB project I need to create a unique string of alphanumeric characters 4 in length from a numeric string 8 in length.This numeric string will always be 8 in length and could range from 00000001 through to 99999999
I have a DLL that I am importing:Declare Function QueryInfo Lib "mydllname" (ByVal DevName As String, ByVal pcQueryParam As String, ByVal Result As String, ByVal Length As Int32) As Int32
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Anyone have an idea what the issue could be? If I run similar code in VB6 (only diff is mtStatus = String(mtValueSize, Chr$(0)) ) it returns what I expect.
I have built a DataTable from my database. Then I am looping through the rows and trying to access a string, however the value is being returned as each character in the string.
For Each theseRows In DisplayForm.MainTab.Rows If theseRows.Item("Last_Name") = userLast And theseRows.Item("First_Name") = userFirst Then
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The Trap_Code values are two or three letter strings, the returned value is each letter once at a time. The loop seems to cycle through the individual characters of the string as an array rather than display the entire value, which is what I was hoping for.
If checkboxList.Items(i).Selected Then .Fields("DESC1").Value += checkboxList.Items(i).Text + ", " End If
should produce output such as "A, B, C,(space)", which will then be bound to a dynamically created GridView. I would like to remove the last two-char string, that is ",(space)". How can I do this?
Basically the first letter of a string must be a certain letter. At the moment the only way I know how to do it is as follows: If sConsignmentNo(0) = "J" Or sConsignmentNo(0) = "C" Or sConsignmentNo(0) = "U" Or sConsignmentNo(0) = "N" Or sConsignmentNo(0) = "H" Or sConsignmentNo(0) = "S" Or sConsignmentNo(0) = "V" Then Basically listening the same thing out over and over. Is there a way I can say, If sConsignmentNo(0) = ListOfValidEntries i.e J,C,U,N etc? Using Visual Basic 2008 and cant use regex!
I have written my own function, which in C would be declared like this, using standard Win32 calling conventions:int Thing( char * command, char * buffer, int * BufSize);I have the following amount of VB figured out, which should import the dll and call this function, wrapping it up to make it easy to call Thing("CommandHere",GetDataBackHere).UPDATE:This code is now a working solution, as shown here:
Imports Microsoft.VisualBasic Imports System.Runtime.InteropServices Imports System Imports System.Text
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Updates: I got the code to build by following the help received here, and then I had forgot the As Return Type (which got me a MarshalDirectiveException PInvokeRestriction). Then I had an assertion failure inside my DLL, which lead to an SEHException. Once fixed, this works BEAUTIFULLY. There are newsgroups where people are saying this can not be done, that VB only loads managed dll assemblies (which I guess is the normal thing most VB users are used to).
my question is how can i check a string for a specific char (for example, in the string:"242.421" theres the char "." how can i make a rule so that char can only be typed once... (in a textbox) so when a user click the "." button on their keyboard it won't allow it again (more than once)