merge cells from Array of Arrays

Hi, sorry if this question have been answered somewhere else but i have an array of arrays that is perfectly exported to xlsx file. What I need is to merge the first 2 cells. to make a sort of title for the table Here is my code so far :

exportFile() {
    /* Format Raw Data reveived */
    let formatedData = this.formatData();
    /* convert state to workbook */
    const ws = XLSX.utils.aoa_to_sheet(formatedData);
    const wb = XLSX.utils.book_new();
      wb = {
        SheetNames:["sheet1"],
        sheet1:{
          "!merges":[
            { s:{r:0,c:0}, e:{r:0,c:1}}
          ]
        }
      }
    XLSX.utils.book_append_sheet(wb, ws, this.state.sheetName);
    /* generate XLSX file */
    const wbout = XLSX.write(wb, { type: "binary", bookType: "xlsx" });
    /* send to client */
    saveAs(
      new Blob([this.s2ab(wbout)], { type: "application/octet-stream" }),
      this.state.fileName
    );
  }

Im using React btw

[reviewher]

You need to build up the worksheet first, then add the merges to the worksheet, then add the worksheet to the workbook: https://jsfiddle.net/1ny97xrb/

/* notice the hole where cell "B1" would be */
var data = [
  ["Merged", "", "C", "D"],
  [1,2,3,4],
  ["a","b","c","d"]
];

/* merge cells A1:B1 */
var merge = { s: {r:0, c:0}, e: {r:0, c:1} };
//var merge = XLSX.utils.decode_range("A1:B1"); // this is equivalent

/* generate worksheet */
var ws = XLSX.utils.aoa_to_sheet(data);

/* add merges */
if(!ws['!merges']) ws['!merges'] = [];
ws['!merges'].push(merge);

/* generate workbook */
var wb = XLSX.utils.book_new();
XLSX.utils.book_append_sheet(wb, ws, "sheet1");

/* generate file and download */
const wbout = XLSX.write(wb, { type: "array", bookType: "xlsx" });
saveAs(new Blob([wbout], { type: "application/octet-stream" }), "issue964.xlsx");

And if this project has been helpful for you, a star would show support 😃

[afifalfiano]

Thank you