fix(exporters): use an array for processing data and fix file corruption #6673

Author: onlyexeption

projects/igniteui-angular/src/lib/services/excel/excel-exporter.ts

@@ -54,34 +54,19 @@ export class IgxExcelExporterService extends IgxBaseExporter {
     @Output()
     public onExportEnded = new EventEmitter<IExcelExportEndedEventArgs>();
 
-    private static populateFolder(folder: IExcelFolder, zip: JSZip, worksheetData: WorksheetData): any {
+    private static async populateFolderAsync(folder: IExcelFolder, zip: JSZip, worksheetData: WorksheetData) {
         for (const childFolder of folder.childFolders(worksheetData)) {
             const folderInstance = ExcelElementsFactory.getExcelFolder(childFolder);
             const zipFolder = zip.folder(folderInstance.folderName);
-            IgxExcelExporterService.populateFolder(folderInstance, zipFolder, worksheetData);
-        }
-
-        for (const childFile of folder.childFiles(worksheetData)) {
-            const fileInstance = ExcelElementsFactory.getExcelFile(childFile);
-            if (!(fileInstance instanceof WorksheetFile)) {
-                fileInstance.writeElement(zip, worksheetData);
-            }
-        }
-    }
-
-    private static populateFolderAsync(folder: IExcelFolder, zip: JSZip, worksheetData: WorksheetData, done: () => void): any {
-        for (const childFolder of folder.childFolders(worksheetData)) {
-            const folderInstance = ExcelElementsFactory.getExcelFolder(childFolder);
-            const zipFolder = zip.folder(folderInstance.folderName);
-            IgxExcelExporterService.populateFolderAsync(folderInstance, zipFolder, worksheetData, done);
+            await IgxExcelExporterService.populateFolderAsync(folderInstance, zipFolder, worksheetData);
         }
 
         for (const childFile of folder.childFiles(worksheetData)) {
             const fileInstance = ExcelElementsFactory.getExcelFile(childFile);
             if (fileInstance instanceof WorksheetFile) {
-                (fileInstance as WorksheetFile).writeElementAsync(zip, worksheetData, () => {
-                    done();
-                });
+                await (fileInstance as WorksheetFile).writeElementAsync(zip, worksheetData);
+            } else {
+                fileInstance.writeElement(zip, worksheetData);
             }
         }
     }
@@ -97,13 +82,14 @@ export class IgxExcelExporterService extends IgxBaseExporter {
             }
         }
 
+
         const worksheetData = new WorksheetData(data, options, this._indexOfLastPinnedColumn, this._sort, this._isTreeGrid);
         this._xlsx = new JSZip();
 
         const rootFolder = ExcelElementsFactory.getExcelFolder(ExcelFolderTypes.RootExcelFolder);
 
-        IgxExcelExporterService.populateFolder(rootFolder, this._xlsx, worksheetData);
-        IgxExcelExporterService.populateFolderAsync(rootFolder, this._xlsx, worksheetData, () => {
+        IgxExcelExporterService.populateFolderAsync(rootFolder, this._xlsx, worksheetData)
+        .then(() => {
             this._xlsx.generateAsync(IgxExcelExporterService.ZIP_OPTIONS).then((result) => {
                 this.saveFile(result, options.fileName);
                 this.onExportEnded.emit({ xlsx: this._xlsx });

projects/igniteui-angular/src/lib/services/excel/excel-files.ts

@@ -136,12 +136,14 @@ export class WorksheetFile implements IExcelFile {
                     worksheetData.isTreeGridData, maxOutlineLevel));
     }
 
-    public writeElementAsync(folder: JSZip, worksheetData: WorksheetData, done: () => void) {
-        this.prepareDataAsync(worksheetData, (cols, rows) => {
-            const hasTable = !worksheetData.isEmpty && worksheetData.options.exportAsTable;
-            folder.file('sheet1.xml', ExcelStrings.getSheetXML(
-                this.dimension, this.freezePane, cols, rows, hasTable, worksheetData.isTreeGridData, this.maxOutlineLevel));
-            done();
+    public async writeElementAsync(folder: JSZip, worksheetData: WorksheetData) {
+        return new Promise(resolve => {
+            this.prepareDataAsync(worksheetData, (cols, rows) => {
+                const hasTable = !worksheetData.isEmpty && worksheetData.options.exportAsTable;
+                folder.file('sheet1.xml', ExcelStrings.getSheetXML(
+                    this.dimension, this.freezePane, cols, rows, hasTable, worksheetData.isTreeGridData, this.maxOutlineLevel));
+                resolve();
+            });
         });
     }
 
@@ -199,16 +201,16 @@ export class WorksheetFile implements IExcelFile {
     }
 
     private processDataRecordsAsync(worksheetData: WorksheetData, done: (rows: string) => void) {
-        let dataRecords = '';
+        const rowDataArr = new Array(worksheetData.rowCount - 1);
         const height =  worksheetData.options.rowHeight;
         this.rowHeight = height ? ' ht="' + height + '" customHeight="1"' : '';
 
         yieldingLoop(worksheetData.rowCount - 1, 1000,
             (i) => {
-                dataRecords += this.processRow(worksheetData, i + 1);
+                rowDataArr[i] = this.processRow(worksheetData, i + 1);
             },
             () => {
-                done(dataRecords);
+                done(rowDataArr.join(''));
             });
     }