For the header, selecting a partial line is equivalent to selecting the entire line. In other words, WzPreview assumes that the header starts in Column 1 and extends to the end of that line. Remember that the header is optional.

Data records must always start in Column 1, but can end wherever you wish. Data fields cannot span more than one line in the file or extend beyond the end of the data record. Furthermore, two separate data fields are not allowed to overlap.

If you find that the last column of data in your file is occasionally extending beyond the record that you defined for the first line of data, you can prevent these trailing characters from being lost by switching to a freely-formatted read instead of a fixed-format read. Switching to a free format allows WzPreview to read the full width of the last column, in spite of its “ragged right” edge. Switching from fixed to free format (and back again) is done using the Attributes menu of the WzPreview Tool.