delete value in array of byte

[kirubagari]

How about the deletion function.i just modify the insert function to delete function.is it correct.actualy i would like to delete if 04 FF 04 FF (got repeating value) i would like to delete one of the 04 FF.So can i use the function that i modify .The same thing i wana do as insert function but i wana delete this time the condition is if there is repeating value as i mentioned just now.




[CODE=vb]Public Function DeleteByte(pmAr ray() As Byte, pmPosition As Long, ByVal pmNewValue As Byte)
' Function to delete a new byte value into a byte array.
Dim ArrayStart As Long, ArrayEnd As Long
Dim I As Long
ArrayStart = LBound(pmArray)
ArrayEnd = UBound(pmArray) -1
' Expand array to make room for the new value.
ReDim Preserve pmArray(ArraySt art To ArrayEnd)
' If requested position is outside the array, just stick it
' at the start or end as appropriate.
If pmPosition < ArrayStart Then
pmPosition = ArrayStart
End If
If pmPosition > ArrayEnd Then
pmPosition = ArrayEnd
End If
' Unless adding to the end of the array,
' push everything across to make room.
If pmPosition < ArrayEnd Then
For I = ArrayEnd To pmPosition -1 Step -1
pmArray(I) = pmArray(I - 1)
Next
End If
pmArray(pmPosit ion) = pmNewValue
End Function[/CODE]

[Killer42]

I don't think the code is quite right. But before we get into the code, I'd like you to try and state fairly simply, the method to be used. In other words, can you describe to me, in a fairly simple overview, how you would go about removing a value from the middle of an array?

Turning it into code is quite simple, and we'll get that done quite quickly. But first you have to understand what you're trying to code.

I'll give you a hint. It's not the same sort of process as inserting. If you start by shortening the array, you've just thrown away whatever was at the end of it.

[kirubagari]

Actualy are u saying that it is not possible to delete the byte in the middle of array.My problem is now

 04 FF 89 67 87 90 89 04 FF 04 FF 
89 65 67 78 93 78 78 89 84 67 04

i wana delete one of the repeating 04 FF in the array of byte.is it possible in vb?

[kirubagari]

Actualy when i insert one i have delete one of the 04 FF value in my program

The arrangement of array sometime like 04 FF 04 FF.So when i insert one 04 FF,i should delete one 04 FF.so i have to find the position where should i delete,sowhen there is repeating value like 04 FF 04 FF ,so i wana delete 1 of the 04 FF.So i have to check until EOF to find out the location to be deleted.So i think it will be explain problem more clear.

[Killer42]

Certainly it's possible to remove a value from the middle of an array. I'd just like you to think about how you would go about removing one from somewhere in the middle.

You might try thinking of the array as a row of boxes, or something similar. What would be the steps involved in taking one out of the middle and not leaving a gap? If you can explain that in detail, you will be very close to writing the code for it.

(Note, here I'm just talking about the actual removal of a byte. This has nothing to do with deciding what byte to remove.)

[kirubagari]

 
 
04 FF F2 03 37 04 04 FF- F1 03 37 04 04 FF F0 03
37 04 04 FF EF 03 37 04 - [b]04 FF 04 FF[/b] EE 03 37 04
04 FF ED 03 37 04 04 FF- EC 03 37 04 04 FF EB 03

For eg i wana find out where the repeating value of 04 FF 04 FF occur,then i wana delete one of the 04 FF
then i wana merge the array.

 
 
04 FF F2 03 37 04 04 FF - F1 03 37 04 04 FF F0 03
37 04 04 FF EF 03 37 04 - 04 FF EE 03 37 04 04 FF
ED 03 37 04 04 FF EC 03 - 37 04 04 FF EB 03 89 67

This is i wana do after the insertion and do deletion also.How to start?Wana check until EOF and do deletion as the location where there is repeating structure

[Killer42]

You keep jumping ahead. I'm still trying to get you to spell out how you would go about removing a byte from an array. Let's get working tools before we try to use them, huh?

[kirubagari]

sir so how if u give a function that delete byte from array as u give me as insertion function.Like delete a value from array of byte as starting so that i can understand more[/font]

[kirubagari]

how to delete a value from a byte of array.like HELLO.i wana delete the 2nd value.How i can do in vb

[Killer42]

how to delete a value from a byte of array.like HELLO.i wana delete the 2nd value.How i can do in vb

Now that I think about if further, if you are just looking to replace duplicated strings, I think it will be much simpler to work with a string. You probably won't need the "delete a byte" routine.

Let's assume, for the sake of argument, that you have read your file into string variable strText, instead of a byte array. I think the Replace() function might do the fix for you, all in one go, like so...

[CODE=vb]Dim strLookFor As String, strChangeTo As String
strChangeTo = Chr$(&H04) & Chr$(&HFF)
strLookFor = strChangeTo & strChangeTo
strFile = Replace(strFile , strLookFor, strChangeTo)[/CODE]

[kirubagari]

[CODE=vb] public function delete( )

Dim strLookFor As String, strChangeTo As String
strChangeTo = Chr$(&H4) & Chr$(&HFF)
strLookFor = strChangeTo & strChangeTo
strFile = Replace(strFile , strLookFor, strChangeTo)

end sub

[/CODE]
Can i used the function.It can do deletion is it.....is it deleting the repeating value.can i call the function as i did in the insertion part....open the binary file and check it out until EOF to check whether there is repeating structure....an d do replacement..

[Killer42]

Here's a code module containing a function which I think will do the trick. You need to call it, passing the file name, the string to look for (04 FF 04 FF) and the string to replace it with (04 FF). Hopefully, it will do the rest. I haven't tested it, though...

[CODE=vb]Option Explicit
DefLng A-Z

Private strFileData As String, strOriginalData As String

Public Function ZapDuplicates(B yVal strFileName As String, strLookFor As String, strChangeTo As String) As Boolean
' Returned value indicates whether the file was actually changed.
Dim FileNo As Long
FileNo = FreeFile
Open strFileName For Binary Access Read Shared As #FileNo
strFileData = Space$(LOF(File No))
Get #FileNo, , strFileData
Close #FileNo
strOriginalData = strFileData

strFileData = Replace(strFile Data, strLookFor, strChangeTo)
If strOriginalData <> strFileData Then
If MsgBox("Data changed - rewrite file?", vbQuestion + vbYesNo) = vbYes Then
Open strFileName For Output Access Write Lock Write As #FileNo
Print #FileNo, strFileData;
Close #FileNo
ZapDuplicates = True
End If
End If
strOriginalData = ""
strFileData = ""
End Function[/CODE]
I hope you will think carefully about the parameters. If you plug in the actual string "04 FF" I'll be disappointed.

[kirubagari]

[CODE=vb] Private Sub CMDFIND_Click()

If lblFileSpec.Cap tion = "" Then
Exit Sub
End If
txbSearch.Text = "04FF04FF"
picHexDisp.SetF ocus
doHexSearch
End Sub


Private Sub doHexSearch()
On Error Resume Next
Dim HexCtn As Integer
Dim I, J
Dim mMatch As Boolean
Dim foundStartPos As Long
Screen.MousePoi nter = vbHourglass
HexCtn = Len(txbSearch.T ext) / 2
ReDim arrHexByte(1 To HexCtn)
For I = 1 To HexCtn
arrHexByte(I) = CByte("&h" & (Mid(txbSearch. Text, (I * 2 - 1), 2)))
Next I
foundStartPos = prevFoundPos + 1
For I = foundStartPos To (UBound(arrByte ) - (HexCtn - 1))
If arrByte(I) = arrHexByte(1) Then
mMatch = True
' Compare rest bytes
For J = 1 To (HexCtn - 1)
If arrByte(I + J) <> arrHexByte(1 + J) Then
mMatch = False
Exit For
End If
Next J
If mMatch = True Then
Dim k
foundStartPos = I
prevFoundPos = I
k = (foundStartPos + 1) / CLng(mPageSize)
k = NoFraction(k)
pageStart = k * mPageSize + 1
pageEnd = pageStart + mPageSize - 1
If pageEnd > mFileSize Then pageEnd = mFileSize
k = foundStartPos + (HexCtn - 1)
If k > pageEnd Then k = pageEnd
updEditByte
ShowPage True, foundStartPos, k, &HFFFF00, vbRed
Screen.MousePoi nter = vbDefault
Exit Sub
End If
End If
Next I
Screen.MousePoi nter = vbDefault
prevFoundPos = 0
MsgBox txbSearch.Text & vbCrLf & vbCrLf & "Searched to end."
End Sub


Function NoFraction(ByVa l inVal As Variant) As Long
Dim X As Integer
Dim tmp As String
Dim k As Long
tmp = CStr(inVal)
X = InStr(tmp, ".")
If X > 0 Then
tmp = Left(tmp, X - 1)
End If
k = Val(tmp)
NoFraction = k
End Function[/CODE]

This is the function that I did to find out the string 04 FF 04 FF.So assign it to text box and when I click the FIND button it find from beginning of file until end. So is it correct way and give me some comments how I can enhance it on how it can find out the value without I click each time as find next value. So when I find out the value may be I can use the function that you give previously as making 04 FF 04 FF To 04 FF. Need your help?

[Killer42]

The function that I provided in my last post will find and replace all occurrences of the string in the file, not just one.

[kirubagari]

sir am i doing rite sir.So can i use the function to find the string and use the function that u give to replace it