chenhaodong / mew-iview

  function has (browser) {
      const ua = navigator.userAgent;
      if (browser === 'ie') {
          const isIE = ua.indexOf('compatible') > -1 && ua.indexOf('MSIE') > -1;
          if (isIE) {

              const reIE = new RegExp('MSIE (\\d+\\.\\d+);');

              reIE.test(ua);

              return parseFloat(RegExp['$1']);

          } else {

              return false;

          }
      } else {
          return ua.indexOf(browser) > -1;
      }
  }
  
  const csv = {
      _isIE11 () {
          let iev = 0;
          const ieold = (/MSIE (\d+\.\d+);/.test(navigator.userAgent));
          const trident = !!navigator.userAgent.match(/Trident\/7.0/);

          const rv = navigator.userAgent.indexOf('rv:11.0');

  
          if (ieold) {
              iev = Number(RegExp.$1);
          }

          if (navigator.appVersion.indexOf('MSIE 10') !== -1) {

              iev = 10;
          }
          if (trident && rv !== -1) {
              iev = 11;
          }
  
          return iev === 11;
      },
  
      _isEdge () {
          return /Edge/.test(navigator.userAgent);
      },
  
      _getDownloadUrl (text) {

          const BOM = '\uFEFF';

          // Add BOM to text for open in excel correctly

          if (window.Blob && window.URL && window.URL.createObjectURL) {

              const csvData = new Blob([BOM + text], { type: 'text/csv' });
              return URL.createObjectURL(csvData);
          } else {
              return 'data:attachment/csv;charset=utf-8,' + BOM + encodeURIComponent(text);
          }
      },
  
      download (filename, text) {
          if (has('ie') && has('ie') < 10) {
              // has module unable identify ie11 and Edge

              const oWin = window.top.open('about:blank', '_blank');

              oWin.document.charset = 'utf-8';
              oWin.document.write(text);
              oWin.document.close();
              oWin.document.execCommand('SaveAs', filename);
              oWin.close();

          } else if (has('ie') === 10 || this._isIE11() || this._isEdge()) {
              const BOM = '\uFEFF';

              const csvData = new Blob([BOM + text], { type: 'text/csv' });
              navigator.msSaveBlob(csvData, filename);
          } else {
              const link = document.createElement('a');
              link.download = filename;
              link.href = this._getDownloadUrl(text);

              document.body.appendChild(link);
              link.click();
              document.body.removeChild(link);
          }
      }
  };
  
  export default csv;