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Sequential Access Data Files

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Join Date: Feb 2005

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nicole0904 nicole0904 is offline

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Sequential Access Data Files

Feb 2nd, 2005

How do I import a picture from a sequential file. I want the sequential file to have the pathname and filename and that to load the picture as the image.

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Comatose

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Taboo Programmer

Re: Sequential Access Data Files

Feb 2nd, 2005

If I understand you correctly, you want to have a sequential file... that file will have a path in it, to a picture file, that you will load, is this correct?

 Help with Code Tags 
 Visual Basic 4 / 5 / 6 Syntax (Toggle Plain Text) 
dim seqfile as string
dim tmpvar as string
 
open seqfile for input as #1
	line input #1, tmpvar
close #1
 
picture1.picture = tmpvar
dim seqfile as string
dim tmpvar as string

open seqfile for input as #1
	line input #1, tmpvar
close #1

picture1.picture = tmpvar

Similarly, If You want to have 1 sequential file, with multiple paths (to different pictures), then you could read that into a collection as such:

 Help with Code Tags 
 Visual Basic 4 / 5 / 6 Syntax (Toggle Plain Text) 
dim xPaths as new collection
dim seqfile as string
dim tmpvar as string
 
seqfile = "c:\somefile.dat"
 
open seqfile for input as #1
	do until eof(1)
		line input #1, tmpvar
		xPaths.Add tmpvar
	loop
close #1
dim xPaths as new collection
dim seqfile as string
dim tmpvar as string

seqfile = "c:\somefile.dat"

open seqfile for input as #1
	do until eof(1)
		line input #1, tmpvar
		xPaths.Add tmpvar
	loop
close #1

If I'm way out in left field, then please elaborate your question, and I'll be happy to assist you in any further help that you need.

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Join Date: Feb 2005

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nicole0904 nicole0904 is offline

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Re: Sequential Access Data Files

Feb 3rd, 2005

I've found a way around that, which I think will be easier for the user. What I'm shooting for is a program where the user enters in the part number and clicks a button and this pulls the manufacturer and product description with a logo. The manager (I'm hoping) will write the information into the sequential file, or update it as necessary(which I'm told is frequently). Right now my code looks like this:

Private Sub cmdGetInfo_Click()

strProdNo = txtProdNo.Text
Do While Not EOF(1)
Input #1, co, part, dscr, ul

If strProdNo = part Then
lblDscrpt.Caption = dscr
lblCo.Caption = co
If ul = "UL1" Then
imgUL.Visible = True
Else
If ul = "UL2" Then
imgUL2.Visible = True
End If
End If
Else
lblDscrpt.Caption = "Not Found"
lblCo = " "
imgUL.Visible = False
imgUL2.Visible = False

End If
Loop

End Sub

With the code like this when I click the button to bring up the info. I get "Not Found"

So I moved the "Loop" to after "Input #1, co, part, dscr, ul"
This will find the last set of data in the Sequential file, but the first record brings up "Not Found"

I'm still playing around with thing, but any suggestions would be nice!
Thanks!

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Comatose

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Taboo Programmer

Re: Sequential Access Data Files

Feb 3rd, 2005

The INPUT has to be within the loop, in order to loop through the entire file. Also, if you have records AFTER the record that is actually found, that are not containing the part number in strProdNo, Then lblDscrpt and lblCo get set to Not found and nothing. So, Pretend that you have a file with:

 Help with Code Tags 
 Visual Basic 4 / 5 / 6 Syntax (Toggle Plain Text) 
not what you want
not what you want
what you want
not what you want
not what you want
not what you want
what you want
not what you want

Then The Captions Get Reset on the last line of the file, because it's not what you are looking for. You need to do 1 of two things here.... the best way is to beak out of the loop, before it finishes reading the file. So, Your code would look a little something like this:

 Help with Code Tags 
 Visual Basic 4 / 5 / 6 Syntax (Toggle Plain Text) 
Private Sub cmdGetInfo_Click()
 
strProdNo = txtProdNo.Text
Do While Not EOF(1)
	Input #1, co, part, dscr, ul
 
	If strProdNo = part Then
		lblDscrpt.Caption = dscr
		lblCo.Caption = co
		If ul = "UL1" Then
			imgUL.Visible = True
			exit do
		Else
			If ul = "UL2" Then
				imgUL2.Visible = True
				exit do
			End If
		End If
	Else
		lblDscrpt.Caption = "Not Found"
		lblCo = " "
		imgUL.Visible = False
		imgUL2.Visible = False
	End If
Loop
End Sub
Private Sub cmdGetInfo_Click()

strProdNo = txtProdNo.Text
Do While Not EOF(1)
	Input #1, co, part, dscr, ul

	If strProdNo = part Then
		lblDscrpt.Caption = dscr
		lblCo.Caption = co
		If ul = "UL1" Then
			imgUL.Visible = True
			exit do
		Else
			If ul = "UL2" Then
				imgUL2.Visible = True
				exit do
			End If
		End If
	Else
		lblDscrpt.Caption = "Not Found"
		lblCo = " "
		imgUL.Visible = False
		imgUL2.Visible = False
	End If
Loop
End Sub

I'm not sure if that will help or not.... drop a line and let me know. k?

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nicole0904 nicole0904 is offline

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Re: Sequential Access Data Files

Feb 3rd, 2005

That is perfect!
Thanks a bunch!

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Taboo Programmer

Re: Sequential Access Data Files

Feb 3rd, 2005

You're very welcome

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Re: Sequential Access Data Files

Feb 7th, 2005

Ok now I want the user to use a separate program to enter in the information that is read. I've entered in two sets of data to test. I can enter them in fine. They look all right in notepad, but when I run the program that is reading from the file. I get the input past end of file error or it will only read the last set of data entered. I know why I'm getting input past end of file error, there is an extra space after the last entry. I delete that and then it won't find the first entry.

If this isn't clear or you want my code email me