retrieving number from file, adding 1 to it and saving new number to f

[Nugget1]

Hello everyone!

I've created a for loop to save a lab and it's variable to file and the number of students in that lab (initially set to 0) to a text file...like this

<% dim varStudNumb, varNumberNabs, varLineCounter, lab, tfrom, tto
lab = CInt(lab)
tfrom = CDbl(tfrom)
tto = CDbl(tto)
varStudNumb = CInt(varStudNumb)
varStudNumb = 0

'assign variable to hold number submitted
varNumberLabs = Request.Form(&quot;LabNumbs&quot

For varLineCounter = 1 to varNumberLabs
Response.Write &quot;Lab:&quot;
lab = Request.Form(&quot;Labs&quot; & varLineCounter)
Response.Write lab
WriteToFile &quot;Lab:&quot;
WriteToFile Request.Form(&quot;Labs&quot; & varLineCounter)
WriteToFile &quot;Students:&quot;
WriteToFile varStudNumb
WriteToFile vbCrLf
Response.Write &quot;<br/>&quot;
Next
CloseTextFile
%>

i can read the text from file also. like this:

<% 'more code above

'Read the file line by line
Do While Not TextStream.AtEndOfStream
line = textStream.readline

' Do something with &quot;Line&quot;
Response.Write Line %>
<input name=&quot;labSubmit&quot; type=&quot;Submit&quot; value=&quot;Submit&quot;><br/>
<%loop

however, how can i extract a particular variable from file (for this, i need to extract the '0' of students, add 1 to it and then overwrite the 0 with the new number in the text file?). All this must be done when a particular submit button is pressed, according to the lab number chosen...by this i mean:

lab: 1 students: 0 [submit] <---button
lab: 2 studnets: 0 [submit]

when user presses submit button, 1 should be added to students and the new number of students should be saved to file

lab: 1 students: 1 [submit]
lab: 2 students: 0 [submit]
if anyone can help me, i'd really really appreciate it. thankyou! anticipating your reply!

 

[BDC2]

You can't change a part of a text file, you must read the whole text file into a variable or array and write the whole array back to a file changing the number of studends as you do it.

To extract a particular variable from the file you must test each line in a loop and match it to a set of rules.

For example, get the 6th character in the line using

Mid(line,6,1)

Test the follownig character to see if it a space or a number in case lab is 10 or more.

Do the same for the number of students which will be after &quot;students:&quot;

StartNo = InStr(line,&quot;students:&quot+10
Mid(line,StartNo,1)

Again test the following character for double figures.

For string manipulation functions go here

http://msdn.microsoft.com/library/default.asp?url=/library/en-us/script56/html/vsfctmid.asp

Hope this helps,

BDC.

 

[Nugget1]

Indeed that was very useful.

thankyou for your help.

will let you know how i went as i am still working on it, along with other things.

regards,
n

 

[onpnt]

thread333-485850 may give you some direction

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