B4J Question string conversion

[G.Z.]

Hi All,

I need help in string conversion.

I wrote this code:

Dim B3S As String
B3S = "W"
Select B3S

Case 87

Log ("is 87")​

Case "W"

Log ("is W")​

End Select​

In the Select I woudl like to recognise B3S not like X but as 87 (that is the ASCII value of X), how I can convert B3S to jump in Case 87?

Thank you

 

[Erel]

Asc("W") will return 87

 

[G.Z.]

yes is working, but in case Asc(VAR1) if the value of VAR1 is bigger then 128 it give 65533.
Other suggestion pls?

 

[Erel]

Can you post an example?

Asc returns the unicode code point. It can be larger than 128. It is not ASCII.

 

[G.Z.]

Hi,
this is the code.

I'm receiving 5 bytes from UART (B1S,B2S,B3S,B4S,B5S) and I have to take action on their value. The valid value of byte could be from 0 to 255

Sub AStream_NewData (Buffer() As Byte)
[INDENT]Dim s As String = BytesToString(Buffer, 0, Buffer.Length, "ASCII")
s = BytesToString(Buffer, 0, Buffer.Length, "ASCII")
HalfBuffer = HalfBuffer & s
Do While HalfBuffer.Length >= 5
[INDENT]NrLoop = NrLoop + 1
HalfBufferTmp = HalfBuffer.SubString2(0, 5)
B1S = HalfBufferTmp.SubString2(0, 1)
B2S = HalfBufferTmp.SubString2(1, 2)
B3S = HalfBufferTmp.SubString2(2, 3)
B4S = HalfBufferTmp.SubString2(3, 4)
B5S = HalfBufferTmp.SubString2(4, 5)
Log(Asc(B1S) & "." & Asc(B2S) & "." & Asc(B3S) & "." & Asc(B4S) & "." & Asc(B5S))   ' ---->>> LOG is: 65533.1.3.20.2 (byte from UART was 203.1.3.20.2)
Log(B1S & "." & B2S & "." & B3S & "." & B4S & "." & B5S)                                        ' ---->>> LOG is: �....  (byte from UART was 203.1.3.20.2)
B3S = Asc(B3S)
Select B3S
[INDENT]Case 3
[INDENT]Log ("is 3")
If Asc(B1S) = 202 Then    ' <<<<<----- trouble is here, if the value of B1S in more then 127 the value from Asc become 65533
[INDENT]If Asc(B2S) = 1 Then
[INDENT]TAint = Asc(B4S)
TAdec = Asc(B5S)
Log ("TA : " & B4S & "." & B5S)[/INDENT]
End If[/INDENT]
End If[/INDENT]
Case Else
[INDENT]Log (B3S)[/INDENT][/INDENT]
End Select
astream.Write(HalfBuffer.GetBytes("ASCII")) 'ECHO
HalfBuffer = HalfBuffer.SubString (5)[/INDENT]
Loop
NrLoop = 0[/INDENT]
End Sub

In SELECT or IF I need to use the value from 0 to 255 to recognise the value of the data, any suggestion?

 

[Erel]

Please use [code]code here...[/code] tags when posting code.

A string is not a collection of bytes. You cannot treat raw bytes as characters.
Work with the bytes directly.

 

[G.Z.]

How to get bytes from AStream_NewData and move them directly to 5 byte var (ex: B1 B2 B3 B4 B5)?
In this case I can use SELECT ....CASE 202 ?

 

[G.Z.]

I tried this but seem not working:

Sub AStream_NewData (Buffer() As Byte)
     Dim BB(5) As Byte = Buffer
     Log ("BB="&Asc(BB(0)))
     If BB(0) = 202 Then ' <<<--- check if value is 202, byte value is 202 but it IF don't recognise it
          Log ("BB=202")
     Else
          Log ("BB= not 202")
     End If
End Sub

 

[Erel]

Bytes in Android are signed (-128 to 127).

You have two options to compare the values:
1. Only use bytes:

Dim b As Byte = 202
If Buffer(0) = b Then
 ...
Else

2. Convert the byte to unsigned byte (which will be stored in an int):

If ToUnsigned(Buffer(0)) = 202 Then
 ...
Else

...

Sub ToUnsigned (b As Byte) As Int
 Return Bit.And(0xFF, b)
End Sub

Note that you don't need the BB variable. Work with Buffer instead.