Ayman,
It is difficult to answer your question because you provided ambiguous (and incomplete) information. It would have helped us to better understand your situation if you did the following:
- Attached your LabVIEW code (the actual file(s) with extension ".vi") that you are trying to "make work".
- Attach a sample "Excel file" and clarify how the other "Excel files" are the same, or are different.
As Gerd mentioned, new LabVIEW programmers often say "Excel" when they mean ordinary text files read by LabVIEW's "Read Delimited Spreadsheet". If these are saved with the extension ".csv", which means "Comma-Separated Values", and signifies a Text file with rows (of numeric or string) data separated by New Lines and columns separated by commas, Windows will create a "phony" Excel-like Icon for these files, causing many new LabVIEW users to mis-call these "Excel" files.
If this is the type of file you have, combining them into one is easy. Here's how to do it:
- Come up with code that gets you all of the files that you want to read (and combine into a "summary" file). If there is a "pattern" to the file names ("cell_frame1_"<n>), you can use the File Dialog Express VI to return a list of files (in a specified Folder) that "match" a certain pattern. Now you have an Array of "Files to be read".
- Decide on the name of the "Merge" File.
- In a For loop (being fed the Array of Input files),
- Open the Input file.
- With a While loop,
- Read a line from the Input File, and write it to the Output File.
- Stop when you reach the end of the Input file.
- When the For loop ends, close the Merge file. Done.
Note that if your "input" files have a Header (or two), you may need to copy the Header from the first file, and decide to not copy the Header from the remaining files.
OK, so what if you really have Excel files (cell_frame1_1.xlsx)? The Algorithm is basically the same as for Delimited Spreadsheets, except you are not dealing with Text files (which LabVIEW can easily read, one line at a time, which corresponds to reading "rows" and ignoring the fact that there are "column-separating characters" in the line), but with data maintained by Excel. So you need to know how to get rows of Data from Excel, and to put rows of Data to another Excel file.
Eight years ago, I posted a Revised "Generate Excel Report" Example that showed how to write an Excel file with "Rows and Columns of Data" in a specific location in an output Excel "Report". But how do you read an Excel file (to get the data you'll need to write)?
The "trick" is hidden in "Create Report", which allows you to specify a "Template" file that is opened and read when the Report opens. Excel Get Data (and Excel Get Last Row) can "get the Data" from a Template, after which you can close the Template. Now you have a choice -- the simplest thing is to save the 2D data from this first file, read the second file and add the data to the end of the Array, until you read (and concatenated) all the Data, then "Create Report" (without a Template) and (using the Excel Easy Table function) write the (concatenated) data to the Report, then Save Report to File (using the "Output" name) and Dispose Report (to close Excel). Whew!
Whichever method is suitable to your situation (which we would know if you attached your code), I urge you to try to program the appropriate algorithm for yourself. Don't try to do it "all at once" -- start by figuring out how to read a named file (and look at the Data you got from reading the file -- does it match the file contents? Are there the right number of rows and columns?). Once you get one file, test out your ability to determine the "list of files" that you want to process (using the File routines mentioned in the first Algorithm). Did you get all the names, and are they "correct"? Keep adding (small) pieces until you have an entire working routine.
Bob Schor
Search LabVIEW like a graph! 
