Question

My requirement is I need to split a text file and store into a datatable. Refer
the following code and column separator “|” and row separator “^”:

var text = streamReader.ReadToEnd();
var lines = text.Split('^');
var rows = lines.Select(l => new {Line = l, Fields = l.Split('|')});
var colCount = rows.Max(r => r.Fields.Length);

var tblRegistration = new DataTable();
for (int i = 1; i <= colCount; i++)
{
    tblRegistration.Columns.Add("Column" + i, typeof (string));
}

When it is correct format it will work fine.

But end user may upload text file like

adfafdsafsdfsdfs^fsdf|sfsdf|sdfsfd|dfs...

in the first row there is only one column, but there should be four.
In this case how to validate it?

Answer 1

If your desired result is that you fill every column from left to the right it’s easy:

foreach (var row in rows)
{
    var newRow = tblRegistration.Rows.Add();
    newRow.ItemArray = row.Fields;
}

So your example file would generate this DataTable:

Column1            Column2   Column3    Column4
adfafdsafsdfsdfs            
fsdf               sfsdf     sdfsfd     dfs

If you want to throw an exception:

foreach (var row in rows)
{
    if(row.Fields.Length != tblRegistration.Columns.Count)
        throw new Exception("Please upload the correct format");

    var newRow = tblRegistration.Rows.Add();
    newRow.ItemArray = row.Fields;
}