Advanced Excel Export with NPOI in .NET Core: Styling and Formatting Guide
The NPOI library allows .NET applications to generate Excel spreadsheets without requiring Excel to be installed on the server. This guide demonstrates how to programmatically create complex .xls files by defining specific styles, fonts, borders, and cell alignments.InstallationInclude the NPOI library in your project via the NuGet Package Mana ...
Posted on Tue, 30 Jun 2026 18:13:47 +0000 by Gier NL
Handling File Downloads from ASP.NET UpdatePanel Using PostBackTrigger
When triggering file downloads (e.g., Excel exports) from controls inside an UpdatePanel, standard asynchronous postbacks fail because the response stream cannot be modified mid-async request. The solution is to force a full postback for the download button using PostBackTrigger.
1. Configure PostBackTrigger in ASPX
Place the <Triggers> s ...
Posted on Thu, 11 Jun 2026 16:34:46 +0000 by Vizzini
Formatting and Exporting Structured Excel Files with C# and NPOI
using NPOI.HSSF.UserModel;
using NPOI.SS.UserModel;
using NPOI.SS.Util;
using NPOI.XSSF.UserModel;
using System;
using System.Collections.Generic;
using System.Data;
using System.IO;
public IActionResult GenerateInventoryDailyReport()
{
var userId = AuthHelper.GetCurrentUserId();
var reportData = DapperRepository.QueryDataSet(
...
Posted on Sat, 16 May 2026 23:12:04 +0000 by djcee