How to load a excel from database..?

// Create new file.
ExcelFile file = new ExcelFile();
 
// Iterate through all DataTables.
foreach (DataTable dataTable in dataSet.Tables)
{
    // Create new sheet.
    var sheet = file.Worksheets.Add(dataTable.TableName);
 
    // Insert DB data.
    sheet.InsertDataTable(dataTable,
        new InsertDataTableOptions("A1") { ColumnHeaders = true });
}
 
// Save file.
file.Save("DataSet.xlsx");