Android Question B4X Compare two byte arrays

hatzisn

Expert
Licensed User
Longtime User
Is there a direct way to compare two byte arrays other than looping in their incredients?

I send two bytes from the computer and in the Mobile Part I am receiving them correctly
but if I check the following

B4X: 
'Obviously comparing objects
If Buffer = "Ok".GetBytes("UTF8") Then

End if

it always returns false although I send "Ok".GetBytes("UTF8") .
 
Last edited:
Sort by date Sort by votes

Magma

Expert
Licensed User
Longtime User
B4X: 
    If BUFFER.GetBytes("UTF8") = "Ok".GetBytes("UTF8") Then
....

    End If
I think...
 
Upvote 0

Magma

Expert
Licensed User
Longtime User
Upvote 0

stevel05

Expert
Licensed User
Longtime User
B4X: 
If Buffer = "Ok".GetBytes("UTF8")

Comparing for equality like that will test if it the same byte array, not it's contents. You could use the ByteConverter library

B4X: 
 Dim B() As Byte = "OK".GetBytes("UTF8")
    Dim BC As ByteConverter
    Log(BC.StringFromBytes(B,"UTF8") = "OK")

Or java.util.Array class via Javaobject: :

B4X: 
    Dim B() As Byte = "OK".GetBytes("UTF8")
    Dim Jo As JavaObject
    Jo.InitializeStatic("java.util.Arrays")
    Log(Jo.RunMethod("equals",Array(B,"OK".GetBytes("UTF8"))))
 
Last edited:
Upvote 0

hatzisn

Expert
Licensed User
Longtime User
Here is a workaround I came with because I want to use it also in B4i. The string comparison I think that would also work but I couldn't risk loosing non printable characters (in case something like that would happen). Here is the solution :

Compare Two Byte Arrays: 
Private Sub CompareByteArrays(b1() As Byte, b2() As Byte) As Boolean
    If b1.Length <> b2.Length Then Return False
    Dim ii As Long
    For ii = 0 To b1.Length - 1
        If b1(ii) <> b2(ii) Then
            Return False
        End If
    Next
    Return True
End Sub
 
Upvote 0
You must log in or register to reply here.

Similar Threads

  • Question
Android Question Different BYTE() result from 2 Instances of B4XCIPHER
Replies
7
Views
432
Gianni Sassanelli
J
  • Question
Android Question Bytes converter. Can someone help me with my confusion with IntsFromBytes
Replies
6
Views
1K
jimseng
J
  • Question
Android Question Byte Array incompatible with Byte Array...
Replies
15
Views
2K
stefanoxjx
S
  • Question
Android Question Compare Two BitMaps
Replies
1
Views
792
Erel
D
  • Question
Android Question [Resolved] How would I read into multiple numeric vars from a btye array?
Replies
3
Views
1K
DataMiser
D
Menu
Log in
Register
Cookies are required to use this site. You must accept them to continue using the site. Learn more…