excel download in angular

 download(){

    if(this.fromdate2==undefined){

      this.filename="AllIssues";

    }else{

      this.filename=this.fromdate2;

    }

   

   

    this.downloadFile(this.jsonData, this.filename);

  }

 

  downloadFile(data, filename='data') {

    let date;

    if(this.fromdate2==undefined){

   date='';

    }else{

      date='Month: '+this.fromdate2;

    }

    let csvData = this.ConvertToCSV(data, ['ArmyNo','Name', 'Rank','Unit' ,'Issue','ReportedOn', 'ResolvedOn']);

    console.log(csvData);  

    let blob;

    if(date==''){

       blob = new Blob(['\ufeff' + csvData], { type: 'text/csv;charset=utf-8;' });

   

    }else{

      blob = new Blob(['\ufeff' +  date + '\r\n' + csvData], { type: 'text/csv;charset=utf-8;' });

   

    }

    let dwldLink = document.createElement("a");

    let url = URL.createObjectURL(blob);

    let isSafariBrowser = navigator.userAgent.indexOf('Safari') != -1 && navigator.userAgent.indexOf('Chrome') == -1;

    if(isSafariBrowser) {  //if Safari open in new window to save file with random filename.

        dwldLink.setAttribute("target", "_blank");

    }

    dwldLink.setAttribute("href", url);

    dwldLink.setAttribute("download", filename + ".csv");

    dwldLink.style.visibility = "hidden";

    document.body.appendChild(dwldLink);

    dwldLink.click();

    document.body.removeChild(dwldLink);

}

ConvertToCSV(objArray, headerList) {

     let array = typeof objArray != 'object' ? JSON.parse(objArray) : objArray;

     let str = '';

     

     let row = 'S.No,';

     for (let index in headerList) {

         row += headerList[index] + ',';

     }

     row = row.slice(0, -1);

     str += row + '\r\n';

     for (let i = 0; i < array.length; i++) {

         let line = (i+1)+'';

         for (let index in headerList) {

            let head = headerList[index];

             line += ',' + array[i][head];

         }

         str += line + '\r\n';

     }

     console.log(str);

     return str;

     

 }