Arrays

[sripriya Gowri]

I need to read a file having about 10000 records and store the records in an array.....I need to search in this array for a specific record and if found move the record to another array and then populate MSFlexgrid from the 2nd array....
Please help me...I am a beginner in VB

[Cakkie]

in stead of using an array, I would use a recordset. You can create a recordset using ADO without connecting to a real database. A recordset offers you much more flexibility than an array.
Firts thing to do is to create the recordset in memory. You will need to add a refference to ADO (Microsoft ActiveX Data Objects) to the project. This can be done via the project>refference menu. Then the code to create the recordset

dim rst as new ADODB.Recordset
rst.Fields.Append "Field1",adVarChar,50
rst.Fields.Append "Field2",adVarChar,50
rst.Fields.Append "Field2",adVarChar,50
rst.open



Now we have an open recordset, we can start populating it with records. We need to open the text file, read it in line by line, and decide which goes where in the recordset. I'll make the assumption that the fields in that textfile are seperated with a comma.

dim ffile as integer
dim strLine as string
dim ArrFields() as string
ffile = freefile
open "myfile.txt" for input as #ffile

do until eof(ffile)
' read the next line
Line input #Ffile, strLine
' split the array in the fiels, note that this can only be done in VB6, VB5 doesn't support the split function
ArrFields = Split(strLine,",")
' add the record to the recordset
rst.addnew
rst("field1") = ArrFields(0)
rst("field2") = ArrFields(1)
rst("field3") = ArrFields(2)
rst.update
loop



Now we have filled the recordset, we can do some searching on that.

' when someone presses a button called cmdSearch
private sub cmdSearch_Click()
rst.movefirst
rst.find "Field1='" & txtCriteria.text & "'"
if not(rst.eof) then
' we found a record
text1.text = rst("field1")
text2.text = rst("field2")
text3.text = rst("field3")
end if
end sub



I think this is a good, and fast solution for the problem. using arrays in this case is much slower, because when you need to search it, you will have to loop through the entire array, which is way slower than searching a recordset.

Tom Cannaerts
slisse@planetinternet.be

Programming today is a race between software engineers striving to build bigger and better idot-proof programs, and the universe trying to produce bigger and better idiots. So far, the universe is winning -- Rich Cook

[sripriya Gowri]

Thanks for the detailed reply...My problem is that I can't use ADO since I am working on VB 5.0. Is it possible to use ADO with VB 5.0?
I am working iwth VB 5.0 professional edition.Please tell me how to do this using VB 5.0?

[Cakkie]

You can use ADO if you install the Data Access SDk, which can be downloaded from the microsoft website. The latest version is 2.6, but 2.1 will do (i believe this comes with products like Office and stuff, not sure though). Once installed, you should be able to add refference to it in VB, even in VB5.

Tom Cannaerts
slisse@planetinternet.be

Programming today is a race between software engineers striving to build bigger and better idot-proof programs, and the universe trying to produce bigger and better idiots. So far, the universe is winning -- Rich Cook

[nikesh]

U can do one thing . First of all save the file in ur format .then while reading the file read till end with the do ... while eof(1)....... Now when ur in the reading the records for searching simultaneously save it to the array that u'd declared. Now If u get the record(s) then use another array to store them. Now as u r finsished with reading the record. Populate the Flesgrid now with the code as :
Loop
msflexgrid1.row=0
msflexgrid1.col=0
msflexgrid1.text=array(0) ' use the variables instead
end loop

If u need the complete code then I'll give it u by the tomorrow... or u can mail me at :
writetonikeshsinha@hotmail.com or nikesh_sinha@altavista.com