demo: add csv2xlsx demo program

cmd/csv2xlsx/main.go

@@ -0,0 +1,60 @@
+// Copyright 2017 Baliance. All rights reserved.
+
+package main
+
+import (
+	"encoding/csv"
+	"flag"
+	"log"
+	"os"
+	"strconv"
+	"strings"
+
+	"baliance.com/gooxml/spreadsheet"
+	"baliance.com/gooxml/spreadsheet/format"
+)
+
+func main() {
+	flag.Parse()
+	if flag.NArg() != 1 {
+		log.Fatalf("pass a single document as a parameter")
+	}
+	f, err := os.Open(flag.Arg(0))
+	if err != nil {
+		log.Fatalf("error opening: %s", err)
+	}
+
+	cv := csv.NewReader(f)
+	wb := spreadsheet.New()
+	sheet := wb.AddSheet()
+	for {
+		rec, err := cv.Read()
+		if err != nil {
+			break
+		}
+		// one row per CSV row
+		row := sheet.AddRow()
+		for _, c := range rec {
+			cell := row.AddCell()
+			// go ahead and use SetNumber/SetString so the cell types get set
+			// correctly, in practice this doesn't matter too much as Excel will
+			// automatically treat number-like string as numbers.
+			if format.IsNumber(c) {
+				v, _ := strconv.ParseFloat(c, 64)
+				cell.SetNumber(v)
+			} else {
+				cell.SetString(c)
+			}
+		}
+
+	}
+
+	if err := wb.Validate(); err != nil {
+		log.Fatalf("error validating spreadsheet: %s", err)
+	}
+
+	outFile := strings.Replace(flag.Arg(0), ".csv", ".xlsx", -1)
+	if err := wb.SaveToFile(outFile); err != nil {
+		log.Fatalf("error saving spreadsheet: %s", err)
+	}
+}