c# precompile a large array or other solution to embed large data in executable

Question

I have to fill a excel file in my app, open, write and close.

The problem is that file contains a lot of format and macros (is a company template) and I realized that will be extremely hard to re-generate from C# and most important, to maintain.

So I opened excel template with a hexeditor, took all bytes as array like this

namespace myapp
{

    public static class ReviewTemplate // exported with HXD
    {
        public static string name = "AS-04522-EN";
        public static byte[] rawData = {
    0xD0, 0xCF, 0x11, 0xE0, 0xA1, 0xB1, 0x1A, 0xE1, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x3E, 0x00, 0x03, 0x00, 0xFE, 0xFF, 0x09, 0x00, 0x06, 0x00, 0x00, 0x00,
...
...
...
}
}

Then, generate from C# like this

File.WriteAllBytes(ReviewTemplate.name + DateTime.Now.ToString("_dd_MM_yyyy_HH_mm_ss") + ".xls", ReviewTemplate.rawData);

It works wonderful except that all array file (*.cs) has 15MB and when I double click any function name in C# for refactor or something, the .NET hangs several minutes.

So the big question is, how can I pre-compile somehow this array.cs file so .NET use as it is? Perhaps put all in some dll? In C I's use the *.obj file.

EDITED

To be more clear, after I generate the required excel (that have 2.5MB anyhow) i use interop to open, write then close.

Is it possible to embed all this data and write somehow in memory, then save finally as excel file on disk?

Thanks,

The IDE is perf-tuned for the kind of code that humans write. They don't write code like that. Short from the effort, it is impossible to maintain. Use Project > Properties > Resources. — Hans Passant, Apr 25 '17 at 17:08

Soonts · Accepted Answer · 2017-04-25T17:20:36.093

5

If you want the template to be inside your .exe/dll, add the .xls to your C# project, right click, properties, set build action to “Embedded resource”.

When you’ll need to fill it, call Assembly.GetManifestResourceStream to open the stream of that embedded resource, then use CopyTo instead of WriteAllBytes.

Update: example (untested)

Stream source = Assembly.GetExecutingAssembly().GetManifestResourceStream( ... );
string destName = "AS-04522-EN" + DateTime.Now.ToString("_dd_MM_yyyy_HH_mm_ss") + ".xls";
using( Stream dest = File.Create( destName ) )
    source.CopyTo( dest );

edited Apr 25 '17 at 17:20

answered Apr 25 '17 at 17:05

Soonts

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I'm not sure I understand... 1. embed as a resource (blob) and using it's bytes by opening a stream or 2. embed as resource (blob) and cast somehow directly from memory as excel file.. this is possible (I already edit the question)? – yo3hcv Apr 25 '17 at 17:10
Probably it works in 4.0 but not in my case :( I use 2.0 (C# 2008 express). However, I accepted your solution and I will try to figure out how to write those bytes :) – yo3hcv Apr 25 '17 at 17:33
Working, but still the input stream is NULL. I use Stream source = Assembly.GetExecutingAssembly().GetManifestResourceStream("AS-04522-EN_Review_Template_v21"); and this is the file name without extension loaded as resource. – yo3hcv Apr 25 '17 at 17:45
1

you're the man! Thank you! It turns out that one should NOT load the resource via Properties, but just insert into project as any file, then set from it's properties to be as "Embeded Resource". – yo3hcv Apr 25 '17 at 17:56

c# precompile a large array or other solution to embed large data in executable

1 Answers1