A client wants to "Web-enable" a spreadsheet calculation -- the user to specify the values of certain cells, then show them the resulting values in other cells.
(They do NOT want to show the user a "spreadsheet-like" interface. This is not a UI question.)
They have a huge spreadsheet with lots of calculations over many, many sheets. But, in the end, only two things matter -- (1) you put numbers in a couple cells on one sheet, and (2) you get corresponding numbers off a couple cells in another sheet. The rest of it is a black box.
I want to present a UI to the user to enter the numbers they want, then I'd like to programatically open the Excel file, set the numbers, tell it to re-calc, and read the result out.
Is this possible/advisable? Is there a commercial component that makes this easier? Are their pitfalls I'm not considering?
(I know I can use Office Automation to do this, but I know it's not recommended to do that server-side, since it tries to run in the context of a user, etc.)
A lot of people are saying I need to recreate the formulas in code. However, this would be staggeringly complex.
It is possible, but not advisable (and officially unsupported).
You can interact with Excel through COM or the .NET Primary Interop Assemblies, but this is meant to be a client-side process.
On the server side, no display or desktop is available and any unexpected dialog boxes (for example) will make your web app hang – your app will behave flaky.
Also, attaching an Excel process to each request isn't exactly a low-resource approach.
Working out the black box and re-implementing it in a proper programming language is clearly the better (as in "more reliable and faster") option.
Related reading: KB257757: Considerations for server-side Automation of Office
You definitely don't want to be using interop on the server side, it's bad enough using it as a kludge on the client side.
I can see two options:
Figure out the spreadsheet logic. This may benefit you in the long term by making the business logic a known quantity, and in the short term you may find that there are actually bugs in the spreadsheet (I have encountered tons of monster spreadsheets used for years that turn out to have simple bugs in them - everyone just assumed the answers must be right)
Evaluate SpreadSheetGear.NET, which is basically a replacement for interop that does it all without Excel (it replicates a huge chunk of Excel's non-visual logic and IO in .NET)
Although this is certainly possible using ASP.NET, it's very inadvisable. It's un-scalable and prone to concurrency errors.
Your best bet is to analyze the spreadsheet calculations and duplicate them. Now, granted, your business is not going to like the time it takes to do this, but it will (presumably) give them a more usable system.
Alternatively, you can simply serve up the spreadsheet to users from your website, in which case you do almost nothing.
Edit: If your stakeholders really insist on using Excel server-side, I suggest you take a good hard look at Excel Services as #John Saunders suggests. It may not get you everything you want, but it'll get you quite a bit, and should solve some of the issues you'll end up with trying to do it server-side with ASP.NET.
That's not to say that it's a panacea; your mileage will certainly vary. And Sharepoint isn't exactly cheap to buy or maintain. In fact, short-term costs could easily be dwarfed by long-term costs if you go the Sharepoint route--but it might the best option to fit a requirement.
I still suggest you push back in favor of coding all of your logic in a separate .NET module. That way you can use it both server-side and client-side. Excel can easily pass calculations to a COM object, and you can very easily publish your .NET library as COM objects. In the end, you'd have a much more maintainable and usable architecture.
Neglecting the discussion whether it makes sense to manipulate an excel sheet on the server-side, one way to perform this would probably look like adopting the
Microsoft.Office.Interop.Excel.dll
Using this library, you can tell Excel to open a Spreadsheet, change and read the contents from .NET. I have used the library in a WinForm application, and I guess that it can also be used from ASP.NET.
Still, consider the concurrency problems already mentioned... However, if the sheet is accessed unfrequently, why not...
The simplest way to do this might be to:
Upload the Excel workbook to Google Docs -- this is very clean, in my experience
Use the Google Spreadsheets Data API to update the data and return the numbers.
Here's a link to get you started on this, if you want to go that direction:
http://code.google.com/apis/spreadsheets/overview.html
Let me be more adamant than others have been: do not use Excel server-side. It is intended to be used as a desktop application, meaning it is not intended to be used from random different threads, possibly multiple threads at a time. You're better off writing your own spreadsheet than trying to use Excel (or any other Office desktop product) form a server.
This is one of the reasons that Excel Services exists. A quick search on MSDN turned up this link: http://blogs.msdn.com/excel/archive/category/11361.aspx. That's a category list, so contains a list of blog posts on the subject. See also Microsoft.Office.Excel.Server.WebServices Namespace.
It sounds like you're talking that the user has the spreadsheet open on their local system, and you want a web site to manipulate that local spreadsheet?
If that's the case, you can't really do that. Even Office automation won't help, unless you want to require them to upload the sheet to the server and download a new altered version.
What you can do is create a web service to do the calculations and add some vba or vsto code to the Excel sheet to talk to that service.
Related
This is more of an advise / best practice question that I'm hoping someone has come across before and can give me a steer.
I need to build a web application (the client would like webforms because that's what their developers know for when i hand it over)
Essentially when the client logs in, they will pick a language then I need to replace the text for menus, input boxes etc. The client wants to add their translations and update them at any time.
Ideas I have looked at are:
Holding the translations in resource files, building an editor in to the web application and then adding attributes on the fly to my viewmodels.
Holding the translations in sql server so i have the name, language and translation as a lookup e.g. Home | French | Maison. Then on pre-render I'll scrape the screen for any controls needing translation in the menu, labels, text areas.
Does anyone know of any good examples or had the experience of doing this themselves.
I've a similar situation, and chose to store data in SQL.
Translation mistakes happen often, and you don't want to recompile or disassemble every time.
It is possible to avoid the need to republish, but I've found it just more intuitive and straightforward to maintain SQL.
Bottom line, it depends on the amount of data you have. If it's more than just a couple of keywords, it sounds like a job for SQL to me.
Edit:
In a similar question, users recommend using resources, claiming it is the standard method.
However, if your users are going to make changes to values on regular basis (not because of mistake correction, but because data actually changes), then SQL seems best fit for the job.
I shall try and keep my scenario as brief as possible and to the point.
The office I’m currently working for uses Lotus Smartsuite on Windows 98 / XP, using lots of Lotus Script to tie together Lotus 123 and Lotus Word Pro documents. They also make heavy use of the Lotus Object Linking functions. I shall describe its behaviour below:
You can fill rows and columns in a 123 Spreadsheet with data galore, style it and format it any way you like and define it as a range (nothing unique here). However, you can then copy that range and paste it as a link in a Lotus Word Pro document. This link is then categorised by its range name, so expanding the range back in the 123 file causes the table in the Word Pro Document to expand. This link also carries with it all the formatting and styling of the cells in the 123 Spreadsheet. As I imagine you are now aware, this link is completely live, you can double click anywhere in the object and it opens up the 123 file for editing, and all changes go backward and forward between the two documents. Most of the data retrieved from testing equipment is stored in these 123 spreadsheets and then parts of that are linked into a final Lotus Word Pro report document sent to the customer.
Note: Just to be clear, this is NOT the same as a DDE link in Open Office, which seems to allow for copying of a non-defined range of cells to be imported into a document where all formatting is lost and editing back and forth is not straight forward. It also behaves differently to an OLE object, which seems to only import the entire Spreadsheet rather than a small subsection of it.
However, in recent years, support this older software (Lotus) is becoming more difficult, especially with regards to sending customers documents (Lotus word Pro files are generally unsupported by more modern Office Tools) and technical support for Lotus Smartsuite seems to be practically non-existent these days. Also, with the fear of on going development in a scripting language no-longer being practised by mainstream IT technicians, on-going development and support seems futile. Once the guys who wrote it move on to other things, we will be left with spaghetti script in a language nobody can help us with.
So, we have this goal of "modernising" our IT system by the end of the year. Linux is becoming a very viable option too (No doubt Debian or a derivative), but Open Office doesn't seem to have the linking capability mentioned above. The reason this linking is so important is because the veterans of the office are so used to working this way - storing data in the spreadsheet, linking back to it later in their Word Pro documents, etc. I think they are more than keen to keep this practice going and we have found no equivalent of it in modern office tools (as was requested of me). I can see, as a software engineer (fluent in many languages), how this practice is not the safest or best way of using and storing data (databases spring to mind), but I was wondering if someone could give me a few other good reasons as to why this is bad practice in the work place (I was always in the belief that you should keep your data away from your reporting and formatting, the two should never be entwined - this looks like spreadsheet hell to me) ... or why this is a good thing to keep doing!?
So, for those of you still with me, I guess what I am asking is:
Is this practice of storing data, formatting it in spreadsheets and importing that directly back and forth between word documents good or bad, and what can be done about it? I guess I'll need to prove my point in case either way for this.
Are there ANY modern alternatives to this linking method (regardless of weather it is good or bad practice or not) out there for Linux or Windows? This link MUST carry formatting as well as dynamic range sizes (DDE links don't seem to be the answer).
What would your solution be if you had to start from scratch? Store everything in databases and use SQL to simply ask for the data you need in your word documents? How would you do this? What software would you use?
Any help with this scenario would be more than helpful, or if you know anywhere I should go to ask for advice, that would be appreciated too.
Thank-you for reading!
My suggestion is to first take a step back. What is the benefit to the way things are done now? Is it just a habit that is tough to break? Is there any reason the documents and spreadsheets need to be maintained and linked the way they are, or is it just a requirement because 'that's how it was done before'?
If you can remove that requirement, you have a lot more options and you're building a system that's easier to understand and maintain.
Regarding question 1, I believe there's nothing wrong with storing data in spreadsheets, especially if the end-users need to create and maintain them and development staff is limited. Some questions are whether that data needs to be secured, is related between spreadsheets, is duplicated across the company, or should be shared in a better way across the company. If any of those are true then a centralized database would make more sense. Personally I'd want any valuable data safely stored in a database where it can be managed, access to it can be controlled, it can be easily backed-up, etc.
Regarding question 2, you can do the same thing in Microsoft Office. You can either link the documents, so that the data stays in the source excel doc but appears in the word doc, or you can embed the excel spreadsheet within the word doc.
You might want to look at Microsoft Access for storing the data and generating reports. Or you could build an application using a relational database back-end and reporting front-end. The possibilities are wide-open. It really depends on where the expertise lies within the company.
If it were me I'd probably use a SQL Express back-end (it's free) and a custom ASP.NET MVC application for generating the reports, but that's just where my expertise lies.
I have a question about storing site configuration data.
We have a platform for web applications. The idea is that different clients can have their data hosted and displayed on their own site which sits on top of this platform. Each site has a configuration which determines which panels relevant to the client appear on which pages.
The system was originally designed to keep all the configuration data for each site in a database. When the site is loaded all the configuration data is loaded into a SiteConfiguration object, and the clients panels are generated based on the content of this object. This works, but I find it very difficult to work with to apply change requests or add new sites because there is so much data to sift through and it's difficult maintain a mental model of the site and its configuration.
Recently I've been tasked with developing a subset of some of the sites to be generated as PDF documents for printing. I decided to take a different approach to how I would define the configuration in that instead of storing configuration data in the database, I wrote XML files to contain the data. I find it much easier to work with because instead of reading meaningless rows of data which are related to other meaningless rows of data, I have meaningful documents with semantic, readable information with the relationships defined by visually understandable element nesting.
So now with these 2 approaches to storing site configuration data, I'd like to get the opinions of people more experienced in dealing with this issue on dealing with these two approaches. What is the best way of storing site configuration data? Is there a better way than the two ways I outlined here?
note: StackOverflow is telling me the question appears to be subjective and is likely to be closed. I'm not trying to be subjective. I'd like to know how best to approach this issue next time and if people with industry experience on this could provide some input.
if the information is needed for per client specific configuration it is probably best done in a database with an admin tool written for it so that non technical people can also manage it. Also it's easier that way when you need versioning/history on it. XML isn't always the best on that part. Also XML is harder to maintain in the end (for non technical people).
Do you read out the XML every time from disk (performance hit) or do you keep it cached in memory? Either solution you choose, caching makes a big difference in the end for performance.
Grz, Kris.
You're using ASP.NET so what's wrong with web.config for your basic settings (if it's per project deploy), then as you've said, custom XML or database configuration settings for anything more complicated (or if you have multiple users/clients with the same project deploy)?
I'd only use custom XML documents for something like a "site layout document" where things won't change that often and you're going to have lots of semi-meaningless data (e.g. 23553123). And layout should be handled by css as much as possible anyway.
For our team XML is a good choice (app.config or web.config or custom configuration file, it depends), but sometimes it is better to design configuration API to make configurations in code. For example modern IoC containers has in-code configuration APIs with fluent interfaces. This approach can give benefits if you need to configure many similar to each other entities or want to achive good human readability. But this doesn't works if non-programmers need to make configurations.
I've been looking into ASP.NET Dynamic Data and how it does scaffolding and routing. I've only scratched the surface, but it's looking like I'd have to create a template for each table that I didn't want to display all columns the same way.
My first impression after looking at dynamic data is that it would seem like less time on the programmer to have to edit one-time generated user controls rather than build a template for each table that doesn't have a uniform display behavior.
What proven solutions are people currently using that help ease the laborious tasks of creating ASP.NET CRUD type user controls?
Thanks
In ASP.NET webforms we use CodeSmith. From a single entity we generate admin pages, codebehinds, service layers, data layers and db stored procedures. All in a matter of seconds. I'd recommend you check it our for quickly building the crud in your apps.
We're actually working on our own code generation tool. It has already proven to work perfectly on the lower layers and now we're on the way to extend it for the presentation layer, that is for generating user controls.
I've not looked into dynamic data (although I'd like to when I have some time) but my biggest fear is always to lose flexibility. The problem is that these front-ends are then maybe generated dynamically each time based on some template and editing, especially bringing in special customer wishes becomes quite difficult. For small standard apps it may work perfectly though.
What we're therefore doing is to "generate" these usercontrols based on a set of standard custom server controls we've developed, but we'll generate just the first time from some static information about the entities in our application. Then you can continue customizing.
Such systems should help the developer, improving his development speed, doing the initial awkward work but then they should give him the flexibility to modify till the maximum. They should not add additional complexity...
I used .netTiers CodeSmith templates long time ago (years) and it was proven so strong, so, it must be more than great now.
I know a (big) company who have built a customization engine (allowing GUI for internal company options) around those templates to use them in most of their applications and were so successful.
I've used http://www.ironspeed.com/ in the past which has been great. Saved us MONTHS of time on our last project which has a big DB, so the cost is worth it. But it looks a bit ugly and can be tricky to update the DB schema once you've generated.
Obviously not much widespread use out there other than whats provided in Visual Studio.
Have a look at Blinq.
I'm looking for the best solution to allow our users to upload XLS spreadsheet so that they can be used to populate tables in our data warehouse (DW).
Our users are heavy Business Object (BO) users, and BO lets you export to XLS. When they have data in a spreadsheet that needs to be loaded to the DW, they need a process to upload the data in the XLS to the DW's db. As a result, we end up with many of these "interfaces" when I think that what we really need is a programmatic automated feed. Using Excel as a data source for inter-system feeds, in my gut, just seems like a bad idea to me.
Question #1: I'd like to see if you agree and why or why not.
OK, there is no swimming against that tide, so I now take as a given that XLS uploads are here to stay for us. Now I need to find the best solution. First, I'll explain what we do now and then what I don't like about it:
Via web pages, we provide empty XLS files (no rows) with a defined set of columns. Each file is intended to be used to update a different target dest table. In each spreadsheet is an "upload" button. Pushing the Upload button results in the macro in the spreadsheet serializing the contents of the file to CSV and FTPing the data to server folder. Periodically, a scheduler fires off an Informatica ETL job that uses the CSV file as input and loads the data into a custom XLS-specific staging table and then, if the records pass edits, into the appropriate target table. Any errors encountered are logged to an error table. For each XLS file uploaded, the data ends up in a separate staging and error table that is specific for the file.
Some of the things I don't like include about our process are:
1) The macro code in the XLS is too exposed, includes passwords for example, can be tampered with and there are issues ensuring that the users are using the latest XLS templates.
2) Business Rule edits are placed in the ETL program, where they should probably be, but because we would like to catch the errors ASAP, i.e, in the spreadsheet, edits are also added to the macro code. This results in duplication of business edits. I want these rules in one place and centrally controlled. IMHO, I think putting any macro code in the XLS introduces a maintenance issue, even calls to stored procedures (some of which we have) or calls to web services (we haven't yet tried to call .NET Web Services from XLS macros.)
3) Every XLS file upload template has its own process with distinct set of staging and error tables and a custom screen for reporting errors encountered. It seems like we need a more generalized re-usable solution.
Besides often getting data exported to XLS from BO, the users like also Excel because it is easier to edit a large number of records and less clunkier than editing individual records via a web interface.
This is the general direction that I am thinking:
First, I want the users to have the ease of editing of Excel with editing, but without including embedded macros in the spreadsheet. I experimented with Farpoint's Grid with Excel compatibility...
http://www.fpoint.com/netproducts/spreadweb/tour/excel.aspx
...and I found that it was quite easy to allow a user the ability to open up an XLS file that resides on their PC and have it open up in a browser and be able to easily access the data read from server-side .NET web code. Excel isn't running locally in their browser, but the functionality of Excel is reproduced, presumably through a lot of client sided scripting that I expect would be a real pain to duplicate myself. You can even cut and paste from a local spreadsheet into the web's spreadsheet. This sounds great, by biggest problem is cost. Our company is near death and won't allow us to purchase any new software.
Next, I want to identify the common components across all spreadsheet upload processing and come up with generic processing code. For example, I imagine a table which defines each of our spreadsheets and the format of each including the column names and data type definitions, perhaps in terms of their destination columns instead of hard coding. Based on this table template definition, I can generate XLS templates for download from this table definition. I can also perform simple generic edits to ensure that the data entered matches the table definition. And one common web page can be used to present the data and allow report data type mismatch errors and allow for the user to correct them. I would also define a common table for storing the data in a "staging" table, using a table with two columns, submission #, row num, name and value, perhaps. No more "custom everything" is the goal.
Next I need to decide where to put the business rules. My dept's mgt firmly believes that all loading of data should be done by Informatica ETL batch processes and therefore the rules/edits belong "in Informatica". I have zero experience with Informatica tools, I am more of a .NET guy. I am therefore unsure as to how these rules are implemented but I suspect that they are not reusable in the sense that they can be used by a .NET web page to validate a particular record against. You see, in some cases, when the user is not performing a bulk upload, they do have the ability to edit a specific record and I would like the same edits that were applied by the ETL bulk insert process to be applied to an individual update attempt to a single record via a web page. If the solution to write a single web service or stored procedure that can be called from either the web page doing an update of a single record or called thousands of times for each record in a bulk upload? The latter sounds inefficient.
Your thoughts on anything above would be very much welcomed.
From a cost perspective, the efforts you'll need to go through to re-create spreadsheet functionality on the web will exceed the cost of Farpoint or other controls. Even if you made $20 an hour, do you think you could complete a working product in under 2 weeks? I think you have the facts on your side when you discussed maintenance issues if you allow ETL functionality to exist in Excel - you have twice the amount of work to maintain the transformation rules. I think you need to convince management that in order to create a maintainable, robust solution you need some flexible utilities.
Farpoint is a good choice. There is also SpreadsheetGear that is a .Net engine that interprets Excel macros and can run on a web server. It has a Win32 control that allows you to create a WinForms solution with very Excel interface functionality. Last time I checked there was no web control for the product. It does an excellent job of providing Excel capability for processing large amounts of data.
Good luck. I think you will find a good solution since you seem to have a good grasp of the pro's and con's of all the different potential solutions.