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Android Question String in to binary file
- Thread starter Claudio57
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Hi Erel,
I do not know English and use the Google translator . I have a big problem. I have to make an application that works with binary files. Must work with binary files because the files are also managed by Windows applications written in VB6 .
In VB6 type is declared like this:
Type Classification
Name As String * 15
Points As Integer
Goal As Integer
end Type
and then there is an array like this:
Public Cla ( 1 To 20 ) As Classification
This array is saved in a binary file with a for next:
For i = 1 To 20
Put # 1 , Cla ( i)
Next i
and when it should be read:
For i = 1 To 20
Get # 5 , Cla ( i)
Next i
I tried to do it in B4A but I can not make it work:
Type Classification ( Name As String , Value As Short , goal As Short )
but when I write I do not know what to do. I tried with:
Dim a As Classification
a.initialize
a.name ="Juventus"
a.points=22
a.goal=19
raf.Initialize ( File.DirRootExternal , " Class.gsc " , False)
raf.WriteObject (a, False , raf.CurrentPosition )
Please if you can help me. Maybe show me a tutorial on the RAF.
I do not know English and use the Google translator . I have a big problem. I have to make an application that works with binary files. Must work with binary files because the files are also managed by Windows applications written in VB6 .
In VB6 type is declared like this:
Type Classification
Name As String * 15
Points As Integer
Goal As Integer
end Type
and then there is an array like this:
Public Cla ( 1 To 20 ) As Classification
This array is saved in a binary file with a for next:
For i = 1 To 20
Put # 1 , Cla ( i)
Next i
and when it should be read:
For i = 1 To 20
Get # 5 , Cla ( i)
Next i
I tried to do it in B4A but I can not make it work:
Type Classification ( Name As String , Value As Short , goal As Short )
but when I write I do not know what to do. I tried with:
Dim a As Classification
a.initialize
a.name ="Juventus"
a.points=22
a.goal=19
raf.Initialize ( File.DirRootExternal , " Class.gsc " , False)
raf.WriteObject (a, False , raf.CurrentPosition )
Please if you can help me. Maybe show me a tutorial on the RAF.
Last edited:
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I understand it. You should however know which encoding is used.
I assume that it is ASCII. What happens if the string is shorter than 15 characters?
You can do something like:
I assume that it is ASCII. What happens if the string is shorter than 15 characters?
You can do something like:
B4X:
Sub WriteClarification(raf As RandomAccessFile, c As ClarificationType)
Dim b() As Byte = c.Name.GetBytes("ASCII")
raf.WriteBytes(b, 0, b.Length, raf.CurrentPosition)
for i = b.Length To 14
raf.WriteByte(0, raf.CurrentPosition)
Next
raf.WriteInt(c.Point, raf.CurrentPosition)
raf.WriteInt(c.Goal, raf.CurrentPosition)
End Sub
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Erel
the length of the file with only one record is 34. It should be 19 (15 Name, 2 Point and 2 Goal). Why?
Hi Erel,
the length of the file with only one record is 34. It should be 19 (15 Name, 2 Point and 2 Goal). Why?
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Il tuo esempio è molto bello e mi da anche degli spunti utili però il mio problema è che i file che ho scritti in VB6 devono essere gestiti sia da PC (Windows) che da Smartphone. I dati integer scritti nel file binario occupano 2 Bytes, gli Int di B4A 4, allora in B4A ho definito Short i tipi relativi ai punti etc. Quando vado a leggerli però mi ritorna dei valori diversi da quelli scritti. Non ho capito perchè e che cosa devo fare.
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