Dump CSV into Excel via powerscript.

csv_into_excel_dump.ps1

Add-Type -ReferencedAssemblies ("Microsoft.Office.Interop.Excel") -TypeDefinition @"
using System;
using System.Collections.Generic;
using Excel = Microsoft.Office.Interop.Excel;

public static class Program {
    public static void Main(string[] args) {
        if (args.Length != 2) {
            Console.WriteLine("Please pass input file name and output file name as arguments.");
            return;
        }
        var inputFilename = args[0];
        var outputFilename = args[1];
        ProcessFile(inputFilename, outputFilename);
    }

    static void ProcessFile(string inputFilename, string outputFilename) {
        string[][] csv;
        using (var sr = new System.IO.StreamReader(inputFilename)) {
            csv = CsvParser.ParseAll(sr);
        }
        Excel.Application excel = new Excel.Application();
        Excel.Workbook workbook = (Excel.Workbook)excel.Workbooks.Add();
        Excel.Worksheet sheet = (Excel.Worksheet)workbook.Worksheets.Add();
        sheet.Name = "Totals";
        for (int i = 0; i < csv.Length; i++) {
            var row = csv[i];
            for (int j = 0; j < row.Length; j++) {
                var cell = row[j];
                sheet.Cells[1 + i, 1 + j] = cell;
            }
        }
        workbook.SaveAs(outputFilename);
        excel.Quit();

        // Release COM objects from memory
        System.Runtime.InteropServices.Marshal.ReleaseComObject(sheet);
        System.Runtime.InteropServices.Marshal.ReleaseComObject(workbook);
        System.Runtime.InteropServices.Marshal.ReleaseComObject(excel);
    }
}

static class CsvParser {
    public static string[][] ParseAll(System.IO.StreamReader sr) {
        List<string[]> csv = new List<string[]>();
        while (true) {
            var line = sr.ReadLine();
            if (line == null) {
                break;
            }
            var row = ParseLine(line, '\t');
            csv.Add(row);
        }
        return csv.ToArray();
    }
    public static string[] ParseLine(string line, char delim) {
        List<string> cols = new List<string>();
        string value = "";

        for (int i = 0; i < line.Length; i++) {
            char at = line[i];
            if (at == delim) {
                cols.Add(value);
                value = "";
                if (i == line.Length - 1) {
                    // It ends with comma
                    cols.Add("");
                }
            } else if (at == '"') {
                cols.Add(ParseEnclosedColumn(line, ref i));
                i++;
            } else {
                value += line[i];
                if (i == line.Length - 1) {
                    // Last character
                    cols.Add(value);                           
                }
            }
        }
        return cols.ToArray();
    }

    static string ParseEnclosedColumn(string line, ref int index) {
        string value = "";
        int numberQuotes = 1;
        int index2 = index;

        for (int i = index + 1; i < line.Length; i++) {
            index2 = i;
            switch (line[i]) {
                case '"':
                    numberQuotes++;
                    if (numberQuotes % 2 == 0) {
                        if (i < line.Length - 1 && line[i + 1] == ',') {
                            index = i;
                            return value;
                        }
                    } else if (i > index + 1 && line[i - 1] == '"') {
                        value += '"';
                    }
                    break;
                default:
                    value += line[i];
                    break;
            }
        }

        index = index2;
        return value;
    }
}
"@ -passthru | Out-Null
[Program]::Main(@(".\DcCsvToExcel\samples\DCP_240320.csv", "output.xlsx"))