Can't output Guid Hashcode

Question

I'm trying to use the hashcode of a guid as a random voucher name for a website, and have been trying to write new records to a SQL table with the Hashcode variable but it doesn't work.

command.Parameters.Add("@voucherName", SqlDbType.NVarChar)
    command.Parameters("@voucherName").Value = Guid.NewGuid().GetHashCode()

When using that code it just puts a whole Guid in the field. How can I make sure it's only going to use a hashcode instead?

Edit

This is the full function used to add the record to my database. It is passed a guid from another function to act as strID

Dim connect As New SqlConnection
    Dim query As String = ""
    connect.ConnectionString = "SERVER = SERVER-SQL01; Trusted_Connection = yes; DATABASE = GlobalPCSQL"
    connect.Open()
    query = "INSERT into dbo.X_WW_VOUCHER_DETAILS (vID, voucherName, expiryDate, validUses, cartOrItem, validStockCode, discountAmount, dollarOrPercent, freebieStockCode, chkCartTotal, cartTotalOverUnder, cartTotalAmount, chkItemPrice, itemPriceOverUnder, itemPriceAmount, chkNoInCart, noInCartOverUnder, noInCartAmount, chkNoOfProduct, noOfProductOverUnder, noOfProductAmount, chkRequiredStockCode, requiredStockCode, category, description) "
    query += "VALUES(@vID, @voucherName, @expiryDate, 1, 0, , 10, 1, , 1, 0, 200, 0,  ,  , 0, , , 0, , , 0, , , Welcome Voucher, 10% off first order over $200. Valid 7 days.)"

    Dim command As New SqlCommand(query, connect)
    command.Parameters.Add("@vID", SqlDbType.UniqueIdentifier)
    command.Parameters("@vID").Value = strID
    command.Parameters.Add("@voucherName", SqlDbType.NVarChar)
    command.Parameters("@voucherName").Value = Guid.NewGuid.ToString().GetHashCode()
    command.Parameters.Add("@expiryDate", SqlDbType.DateTime)
    Dim exDate As DateTime = DateTime.Now
    exDate.AddDays(7)
    command.Parameters("@expiryDate").Value = exDate

    command.ExecuteNonQuery()
    connect.Close()

What's really weird is that whether I use guid.newguid().toString() or strID.toString() to start things off... both vID and voucherName end up with the same guid as their value.

score 2 · Accepted Answer · edited May 23 '17 at 10:26

2

Well, are you looking for a hashcode like this?

"OZVV5TpP4U6wJthaCORZEQ"

Then this answer might be useful:

Guid g = Guid.NewGuid();
string GuidString = Convert.ToBase64String(g.ToByteArray());
GuidString = GuidString.Replace("=","");
GuidString = GuidString.Replace("+","");

Extracted from here. On the linked post there are many other useful answers. Please take a look!

Other useful links:

Edit: Doublechecking your code, you might change it from Guid.NewGuid.ToString().GetHashCode()

to

Guid.NewGuid.GetHashCode().ToString()

edited May 23 '17 at 10:26

Community

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answered Jun 22 '15 at 22:20

Fabian Bigler

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Thanks for the link, I tried it out but for some reason it's still sticking the same guid in both fields. I've changed "@voucherName" to reference the new GuidString variable but it just slaps the same strID (guid) in as the vID field. – Wompguinea Jun 22 '15 at 22:27
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@ChrisHinton I would advise you to debug and step through. Check your hashcode during runtime and see if it's working. You might change your code from Guid.NewGuid.ToString().GetHashCode() to Guid.NewGuid.GetHashCode().ToString(). – Fabian Bigler Jun 22 '15 at 22:32
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You ever realise you've been doing something really stupid and don't want to admit how dense you've been... I managed to forget that my site couldn't reference that function properly (something weird about session state, this site is a mess)... so I copied it into a different page... which was referencing strID.ToString(). Genius. – Wompguinea Jun 22 '15 at 22:40

Can't output Guid Hashcode

1 Answers1