feat(datutil): fixed the merge title issue

Author: susanta96

.npmignore

@@ -3,4 +3,6 @@
 /src/
 .github
 /src-js
+/examples
+node_modules
 

dist/ExcelPlugin/utils/DataUtil.js

@@ -97,14 +97,16 @@ var excelSheetFromDataSet = function excelSheetFromDataSet(dataSet, bigHeading)
         }
       };
       ws['!merges'] = [mergedRange];
-      var mergeRef = xlsx_js_style_1.utils.encode_range({
-        c: xSteps,
-        r: 0
-      }, {
-        c: xSteps + dataSetItem.columns.length - 1,
-        r: 0
-      });
-      getHeaderCell(bigHeading, mergeRef, ws);
+      var cell = {
+        t: 's',
+        v: bigHeading.title,
+        s: bigHeading.style ? bigHeading.style : {
+          font: {
+            bold: true
+          }
+        }
+      };
+      ws['A1'] = cell;
       rowCount += 1;
     }
     var columnsInfo = [];

src-js/ExcelPlugin/utils/DataUtil.js

@@ -74,8 +74,12 @@ const excelSheetFromDataSet = (dataSet, bigHeading) => {
         if (bigHeading?.title) {
             let mergedRange = { s: { c: xSteps, r: 0 }, e: { c: dataSetItem.columns.length - 1, r: 0 } };
             ws['!merges'] = [mergedRange];
-            let mergeRef = xlsx_js_style_1.utils.encode_range({ c: xSteps, r: 0 }, { c: xSteps + dataSetItem.columns.length - 1, r: 0 });
-            getHeaderCell(bigHeading, mergeRef, ws);
+            let cell = {
+                t: 's',
+                v: bigHeading.title,
+                s: bigHeading.style ? bigHeading.style : { font: { bold: true } },
+            };
+            ws['A1'] = cell;
             rowCount += 1;
         }
         let columnsInfo = [];

src/ExcelPlugin/utils/DataUtil.ts

@@ -81,8 +81,12 @@ const excelSheetFromDataSet = (dataSet: ExcelSheetData[], bigHeading?: ExcelShee
         if(bigHeading?.title) {
             let mergedRange: Range = { s: { c: xSteps, r: 0 }, e: { c: dataSetItem.columns.length - 1, r: 0 } };
             ws['!merges'] = [mergedRange];
-            let mergeRef = utils.encode_range({ c: xSteps, r: 0 }, { c: xSteps + dataSetItem.columns.length - 1, r: 0 });
-            getHeaderCell(bigHeading, mergeRef, ws);
+            let cell: CellObject = {
+                t:  's',
+                v: bigHeading.title,
+                s: bigHeading.style ? bigHeading.style : { font: { bold: true } },
+            };
+            ws['A1'] = cell;
             rowCount += 1;
         }