Question

I am wanting to append 6 CSVs that have identical layouts and headers together.

I’ve been able to accomplish this by loading each of the 6 csvs into their own seperate data tables and removing the first row of each datatable. Finally I’ve appended them together using the ImportRow method.

DataTable table1 = csvToDataTable(@"C:\Program Files\Normalization\Scan1.csv");
DataTable table2 = csvToDataTable(@"C:\Program Files\Normalization\Scan2.csv");
DataTable table3 = csvToDataTable(@"C:\Program Files\Normalization\Scan3.csv");
DataTable table4 = csvToDataTable(@"C:\Program Files\Normalization\Scan4.csv");
DataTable table5 = csvToDataTable(@"C:\Program Files\Normalization\Scan5.csv");
DataTable table6 = csvToDataTable(@"C:\Program Files\Normalization\Scan6.csv");

        foreach (DataRow dr in table2.Rows)
        {
            table1.ImportRow(dr);
        }
        foreach (DataRow dr in table3.Rows)
        {
            table1.ImportRow(dr);
        }
        foreach (DataRow dr in table4.Rows)
        {
            table1.ImportRow(dr);
        }
        foreach (DataRow dr in table5.Rows)
        {
            table1.ImportRow(dr);
        }
        foreach (DataRow dr in table6.Rows)
        {
            table1.ImportRow(dr);
        }

        CreateCSVFile(table1, @"C:\Program Files\Normalization\RackMap.csv");

I feel this is clunky and not very scalable but I had trouble dealing with the headers when I tried to append at the CSV level. Any suggestions?

TIA

Answer 1

Get a DirectoryInfo of all files matching the mask *.csv

Create a for loop to iterate the results.

Drop the first row when importing each file.

EDIT:

If you just want to combine the files, rather than import into a data table, you could treat them as text files. Concatenate them, dropping the header line each time. Here is an example:

string myPath = @"K:\csv";

DirectoryInfo csvDirectory = new DirectoryInfo(myPath);
FileInfo[] csvFiles = csvDirectory.GetFiles("*.csv");
StringBuilder sb = new StringBuilder();
foreach (FileInfo csvFile in csvFiles)
    using (StreamReader sr = new StreamReader(csvFile.OpenRead()))
    {
        sr.ReadLine(); // Discard header line
        while (!sr.EndOfStream)
            sb.AppendLine(sr.ReadLine());
    }
File.AppendAllText(Path.Combine(myPath, "output.csv"), sb.ToString());