Question is like this, I want to download when users click on export will be the results of the query to export,

And this is my js

 
Layer. Confirm (' determine export to Excel? '{
BTN: [' sure ', 'cancel'] 
}, function () {
$. Ajax ({
Type: "POST", 
Url:/require/export2Excel, 
ResponseType: Blob, 
Data: {
RequireName: $(' # requireName). Val (), 
RequireId: $(' # requireId). Val (), 
FunctionName: $(' # functionName '). Val (), 
FunctionModule: $(' # functionModule). Val (), 
FunctionType: $(' # functionType). Val (), 
AssignState: $(' # assignState). Val (), 
SubmitState: $(' # submitState). Val (), 
}, success: (wb)=& gt; {//wb for me after the workbook, I written respong excel file when no data directly, as this data, may have a problem here 
Var blob=new blob ((wb));//create a blob object 
Var a=document. The createElement method (' a ');//create a & lt; A>  The tag 
A.h ref=https://bbs.csdn.net/topics/URL.createObjectURL (blob);//the response is a blob 
A. d. ownload="functional requirements tables. XLSX"; 
A.s tyle. Display='none'; 
Document. The body. The appendChild (a); 
A.c lick (); 
A.r emove (); 
Layer. MSG (" export success!" ); 
} 
}) 
}); 

Back-end code is
The controller

 
@ PostMapping (" export2Excel ") 
@ ResponseBody 
Public void export2Excel (@ RequestParam Map Params, HttpServletResponse response) {
Query Query=new Query (params, ""); 
List List=requireService. List (query); 
ExcelUtils. WriteExcel (response, list, FunctionRequireDO. Class); 
} 

Utility class ExcelUtils

 
Public static & lt; T> Void writeExcel (HttpServletResponse response, List DataList Class CLS) {
The Field [] fields=CLS. GetDeclaredFields (); 
List FieldList=Arrays. Stream (fields) 
The filter (field - & gt; {
ExcelColumn annotation=field. GetAnnotation (ExcelColumn. Class); 
If (the annotation!=null & amp; & The annotation. Col () & gt; 0 {
Field. SetAccessible (true); 
return true; 
} 
return false; 
}). Sorted (Comparator.com paring (field - & gt; {
Int col=0; 
ExcelColumn annotation=field. GetAnnotation (ExcelColumn. Class); 
If (the annotation!=null) {
Col=annotation. Col (); 
} 
Return col. 
})). Collect (Collectors. ToList ()); 

Workbook wb=new XSSFWorkbook(); 
Sheet Sheet=wb. CreateSheet (" Sheet1 "); 
AtomicInteger ai=new AtomicInteger (); 
{
The Row Row=sheet. CreateRow (ai) getAndIncrement ()); 
AtomicInteger aj=new AtomicInteger (); 
//write head 
FieldList. ForEach (field - & gt; {
ExcelColumn annotation=field. GetAnnotation (ExcelColumn. Class); 
String columnName=""; 
If (the annotation!=null) {
ColumnName=annotation. The value (); 
} 
The Cell Cell=row. CreateCell (aj. GetAndIncrement ()); 

CellStyle CellStyle=wb. CreateCellStyle (); 
CellStyle. SetFillForegroundColor (IndexedColors. WHITE. GetIndex ()); 
CellStyle. SetFillPattern (cellStyle. SOLID_FOREGROUND); 
CellStyle. SetAlignment (cellStyle. ALIGN_CENTER); 

The Font Font=wb. CreateFont (); 
The font. SetBoldweight (font. BOLDWEIGHT_NORMAL); 
CellStyle. SetFont (font); 
cell.setCellStyle(cellStyle); 
Cell. SetCellValue (columnName); 
}); 
} 
If (CollectionUtils isNotEmpty (dataList)) {
DataList. ForEach (t - & gt; {
The Row row1=sheet. CreateRow (ai) getAndIncrement ()); 
AtomicInteger aj=new AtomicInteger (); 
FieldList. ForEach (field - & gt; {
Class<?> Type=field. GetType (); 
The Object valuehttps://bbs.csdn.net/topics/=""; 
Try {
Value=https://bbs.csdn.net/topics/field.get (t); 
} the catch (Exception e) {
e.printStackTrace(); 
} 
The Cell Cell=row1. CreateCell (aj. GetAndIncrement ()); 
If (the value!=null) {
If (type==Date. Class) {
Cell. SetCellValue (value. The toString ()); 
} else {
Cell. SetCellValue (value. The toString ()); 
} 
Cell. SetCellValue (value. The toString ()); 
} 
}); 
}); 
} 
//freeze panes 
Wb. GetSheet (" Sheet1 "). CreateFreezePane (0, 1, 0, 1); 
//the browser downloads the excel 
BuildExcelDocument (" functional requirements tables. XLSX, wb, response); 
//generates excel file 
//buildExcelFile (" C:/Users/Administrator/Desktop/" + fileName + ". XLSX ", wb); 
} 

/* * 
* the browser downloads the excel 
* @ param fileName 
* @ param wb 
* @ param response 
*/

Private static void buildExcelDocument (String fileName, Workbook wb, HttpServletResponse response) {
Try {
//application/octet stream - 
The response. SetContentType (MediaType. APPLICATION_OCTET_STREAM_VALUE); 
The response. SetHeader (" the content-type ", "application/VND. - ms excel; charset=UTF-8"); 
The response. SetHeader (" the Content - the Disposition ", "legislation; Filename="+ URLEncoder. Encode (filename," utf-8 ")); 

The response. FlushBuffer (); 
Wb. Write (response. GetOutputStream ()); 
} the catch (IOException e) {
e.printStackTrace(); 
} 
} 

I am now writing can be exported to an excel file, but open show


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