I have a list that I am trying to export to excel using the following code with the ClosedXML nuget package and following a guide online:
private async TaskClickExportXLS()
{
await ExportToExcel(js, selectedFlyer.DealNo "_SKY_CAT_Report.xlsx");
}
public async Task ExportToExcel(IJSRuntime js, string fileName)
{
blockProducts = blocks.SelectMany(b => b.Products).Distinct().ToList();
var wb = new XLWorkbook();
var ws = wb.Worksheets.Add("Sku Category Report");
ws.Cell(1, 1).Value = "SKU";
ws.Cell(1, 2).Value = "Product EN";
ws.Cell(1, 3).Value = "Product FR";
ws.Cell(1, 4).Value = "Category";
foreach(var item in blockProducts)
{
ws.Cell(1, 1).Value = item.Sku;
ws.Cell(1, 2).Value = item.ProductEn;
ws.Cell(1, 3).Value = item.ProductFr;
ws.Cell(1, 4).Value = item.MainCategory;
}
MemoryStream XLSStream = new();
XLSStream.Position = 0;
wb.SaveAs(XLSStream);
var XLSSArray = XLSStream.ToArray();
await js.InvokeVoidAsync("BlazorDownloadFile", fileName, XLSSArray);
}
I alsocopied this js runtime file from the guide as well:
function BlazorDownloadFile(filename, content) {
// Create the URL
const file = new File([content], filename, { type: "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet" });
const exportUrl = URL.createObjectURL(file);
// Create the <a> element and click on it
const a = document.createElement("a");
document.body.appendChild(a);
a.href = exportUrl;
a.download = filename;
a.target = "_self";
a.click();
URL.revokeObjectURL(exportUrl);
}
My file downloads but when it opens I get the "Excel cannot open the file because the file format or extension is not valid". I have went online and did research and the things I've tried are the following -
Set the Stream position to 0.
Change the type of the file in my openfile.js to the following: type: "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet"
This does not seem the fix the issue and my code seems to work fine when debugging. Any help would be appreciated!
CodePudding user response:
I had tried to follow that guide and it did not work for me. What I ended up doing is streaming my workbook (wb) into a byte array and passing it as a parameter to a SaveAs function:
var bytes = new byte[0];
using (var ms = new MemoryStream())
{
wb.SaveAs(ms);
bytes = ms.ToArray();
}
await SaveAs(JSRuntime, fileName ".xlsx", bytes);
This is the SaveAs function which is async Task like the comments were suggesting:
async Task SaveAs(IJSRuntime js, string fileName, byte[] data)
{
await js.InvokeAsync<object>(
"BlazorDownloadFile",
fileName,
Convert.ToBase64String(data)
);
}
And here is the js:
function BlazorDownloadFile(filename, bytesBase64) {
var link = document.createElement('a');
link.download = filename;
link.href = "data:application/octet-stream;base64," bytesBase64;
document.body.appendChild(link); // Needed for Firefox
link.click();
document.body.removeChild(link);
}
I believe these are the references I used: https://gist.github.com/danielplawgo/ac4d58837224dba7b6fc51de865b12da https://blazorfiddle.com/s/o8g3elz1