ASP.NET MVC: C# Download file and save as dialog [duplicate] - asp.net

Question

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Setting mime type for excel document
(6 answers)
Closed 9 years ago.
i've written this code which will generate an excel spreadsheet and save it to a specified location. I want to then display a "Save as" dialogue box by reading the file from the stored location and then asking then user where they want to store it.
Excel.Application excelApp = null;
Excel.Workbook wb = null;
Excel.Worksheet ws = null;
Excel.Range range = null;
excelApp = new Excel.Application();
wb = excelApp.Workbooks.Add();
ws = wb.Worksheets.get_Item(1) as Excel.Worksheet;
for(int i = 0; i< 10;++i) {
ws.Cells[i, 1] = i+
}
wb.SaveAs(#"C:\test.xls", Excel.XlFileFormat.xlWorkbookNormal);
wb.Close(true);
excelApp.Quit();
How to download in the following format?
string str = "Hello, world";
byte[] bytes = System.Text.Encoding.UTF8.GetBytes(str);
return File(bytes, "text/plain");

Answer 1

Given that is an Excel doc saved at c:\temp\excelDoc.xls and given that you have a WebForm that has a link like this
<asp:LinkButton runat="server" ID="GetExcel" OnClick="GetExcel_Click">Download</asp:LinkButton>
In your code-behind you can read the file from disk and send to the user by something like this
protected void GetExcel_Click(object sender, EventArgs e)
{
var fileName = "excelDoc.xls";
using (var cs = new FileStream(#"c:\temp\" + fileName, FileMode.Open))
{
Response.Clear();
Response.AddHeader("content-disposition", "attachment; filename=" + fileName);
Response.ContentType = "application/vnd.ms-excel";
byte[] buffer = new byte[32768];
int read;
while ((read = cs.Read(buffer, 0, buffer.Length)) > 0)
{
Response.OutputStream.Write(buffer, 0, read);
}
Response.End();
Response.Flush();
}
}