I have an ASP.Net web page that displays various chunks of data based on a user's search string. In this web page I'm using a <Panel> tag because I need to have a vertical scrollbar that displays when needed to display all of the data.
I've thought about defining an HTML page (in code behind, with all the tags and data included), and displaying that inside a <div>, inside the <Panel>.
I've also explored the possibility of displaying an ASP.Net web page with the data/tags/etc. and placing each page in its own <Iframe> element. I'm afraid that this solution would be slow to load (as compaired to the HTML method described above) especially when there's 100's of individual pages to be loaded.
My question is what's the best way to display N number of individual pages of data and have a vertical scrollbar when there's a need?
Displaying various data pieces on ASP.NET pages is a big subject, I suppose, and many methods can be used, including the ones you've mentioned.
How about making use of Dynamic Data framework .NET v2,3,4. The most powerful is the latest one of course.
Then you don't need to create 100's of individual pages, just onthe fly redirect using metatable names used in your model/context. All you data will also be wonderfully linked where appropriate. Also need to carefully design you model based on however your data needs be presented. The controls for that could be GridView or other, but all done on server side.
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In our current application there is a new requirement of our client.As they told that they need n numbers of forms at different stages of their business and those are changing time to time. Even a new forms can be added. Their requirement is once the product is delivered to them they will not come back to us again and again for each change and will create those form by their own.
Simply they want a user interface where they can create the form by drag and drop manner.
What they want :
In our application there will be a form building section where a non technical person can be able to create a form.
Mapping the controls with existing data of their existing database so that the form is populated with the corresponding data ( data will be inserted into the database using another user interface).
Once the data is populated they will take the print out of the filled up form and will proceed as per their business flow.
As they introduce new form time to time we can't provide any predefined template to them and they are not agree to design the form in HTML.
Is there any way of doing this in Asp.Net MVC (without using any CMS ).
there are a number of asp.net forms builders. And I been wanting to build my own for years. (you store the control, the location etc in a database, or even as xml, and then on page load, read the xml, and crank out the controls and layout into the page. We all built these for desktop, and you can do the same for the web.
The open source evolutility project has a FANTASTIC system for this, but it does NOT include the GUI part. But, it would be a good start. You would have to build the GUI part, but the rendering part, and save of the forms layout is all done for you. So, your forms builder would offer a set of controls to drop and move around in the form. When you save, you would have a corresponding "xml" markup bit that you save to the one "forms layout" file. On forms load, you read that xml file and produce the form (that's the part evolutility does for you). So, you need the part that has each control in a tool box (along with the xml for that control). you drop control into form, and add the xml to the "form layout in xml".
As I stated, evolutility has all the parts to render forms and layout and place controls on the final finished form for display - it just don't have a GUI for doing this part.
You can look at the project here:
http://evolutility.com/
there are others. But, it really depends on how complex of a form builder or content builder you wish to make.
But, a xml, or json based layout and definition of the controls placed on a page is a good start. You could store such "layout" information in a database. Heck have a classic master to child table, and thus save each control in evolutiity format, and simple append then all together, and then have evolutility render that xml into a working form for you.
I don't know of a open source project that combines both the "layout" and "define" of the controls AND ALSO has a GUI to build the forms. But, to be fair, the hard part (how to layout, and how to have each control defined in some json (or xml) is done for you.
We have different clients asking for home page with different design layout so what is an efficient way to have multiple pages with different styles, layout for the same data coming from the database in a mvc project?
You could have different css and change the design according to the user that has logged in. If the different design includes placement of elements in different places, then you could use a grid system and store in JSON (preferably) the schema of the page. Then, on each login you should load the JSON and place the elements accordingly. Hope that gave you a small hint!
Now this is going to be a very absurd question. But what can I do, it's the client's requirement. Basically, we have a grid (master-detail type) that goes up to about 15 thousand plus rows (has the potential to go up to 30-50 thousand rows in a few years time).
My client does NOT want any paging, does not want any data cropped as well. Also he isn't exactly using the latest hardware so rendering on browsers is a big issue. He wants to view everything by printing it out or looking through it on the browser. (You may all think how insane that sounds, and it sure is).
Now I want to resolve this issue by rendering html quickly. At the moment its a simple asp.net grid view w/o paging. That essentially renders HTML tables. My options that I think are:
- Manually rendering html using div (for quick loading)
- export it to pdf or excel (is there any way to export without the need to resort to third party controls?)
- give the finger (to the client :D j/k)
So to sum up, whats the best way to show 10,000 plus records of data on html?
consider using the "Scroller" plug-in for Datatables..
As part of DataTables 1.8 release a new plug-in called "Scroller" was
introduced as part of the download package. Scroller is an
implementation of virtual scrolling for DataTables, which presents a
vertically scrolling table, scrolling the full height of the table,
but drawing only the rows which are necessary for the visible display,
leading to a huge performance increase. This is quite an exciting
plug-in for DataTables not only for the performance increase, but also
because it effectively provide a new user interaction with the table,
allowing full scrolling of very large data sets.
I know this is almost a year late, but in case it helps someone.
Use SlickGrid - It uses divs instead of tables, which gives so much more performance in IE. Check this example
He wants to view everything by printing
This is imho the only viable solution to view all information. PDF or Excel is much better at handling a large number of rows.
Doing the rendering is quite easy. Just set the excel mime type and return a HTML table.
http://www.designdetector.com/archives/05/07/HTMLToExcelTheEasyWay.php
When it comes to PDF, you probably have to use an external library like PDFSharp.
You should do the paging - it does not mean that you need to show only one page of data at a time but rather you should retrieve and render pageful of data at a time (and keep continuously fetching pages one after one till data is finished).
For example, send the first page of data from the server in the initial request. Setup a js timer and use AJAX requests to retrieve subsequent pages of data and load that into the browser. You can have multiple (say 3-4) AJAX requests going on simultaneously for retrieving pages - only thing would be to achieve the ordering correctly in such approach.
I will personally avoid grid-view and render the html table using manual java-script (with help for jquery) or use some java-script template engine. I will use JSON for retrieving the data from the server.
I ran into this problem multiple times in my career, and never was able to find a elegant solution for it. Imagine you have a simple page, that has a repeater. You populate that repeater on the server-side through the databinding. That's great, works fast and does what it's supposed to. But now you want to add paginator to that repeater, or otherwise change the output. Doing it through Ajax is a preferred way to enable rich client interaction.
So you create a web-service that serves you the data as JSON, but now you are stuck... Either you have to write complicated client-side code to find each field that you need to modify in each repeater-item, or you have to blow away the whole server-side output of the repeater and construct new HTML from the scratch, or, the method that I've been using lately, take the first repeated item, blow away everything else and clone the first item as many time as you need to and modify it's fields.
All of the described methods are not optimal, because no matter what, they require quite a bit of repeated logic on the server-side (i.e. template in repeater) and on the client-side (javascript to display JSON data). There's got to be a better, easier way to do this. First thing that comes to mind, is instead of returning JSON from the web-server, return HTML of the pre-populated repeater. But for something like that, I might as well use ASP.NET AJAX Update panel. The output isn't going to be any smaller with a stand-alone web-service.
Next thing that I thought of, is JavaScript templates. What if there would be some way to take unprocessed repeater template on the server-side, and convert it to JavaScript template that could be either embedded on the page at load, or served as part of the web-service response. However, I couldn't find any existing solutions for something like this. And I can't think of a simple way to do that myself. Any ideas?
P.S. Rendering JavaScript template to the client-side on page load, and using JavaScript to populate it without the initial view being rendered on the server (no repeater and databinding) is out of the question. I care too much about performance.
Firstly, I don't believe that using client template with JSON data even on first load will adversely affect the performance unless we are talking about devices with different form factors such as phones etc.
However, if you must use server side templating/rendering then why not make server return the html for the repeater. This can be done by putting repeater logic into a different user control/page and processing only that page on ajax request. And this is not at all equivalent to using UpdatePanel (as stated by you) - UpdatePanel posts entire page data (including view-state) having more request size. The response size is also larges because it must contain the view-state. On server side also, use of UpdatePanel results in loading complete control tree with state data and post-back event processing. Sending only the requisite html is much better approach and will fit your needs perfectly - only issue is the html would be larger in size as compared to JSON.
Lastly, there are some interesting projects such as Script# - Script# converts C# code into java-script. You may build something similar (using script# itself) to convert the server side templating code into eqivalent JS code. More viable approach on similar lines could be use T4 templating to convert a technology-agnostic template into both server side code (markup + code or pure code) and equivalent JS-code.
After thinking about all pros and cons of different approaches, I stopped on the following method. I created a custom ASP.NET databound control, that can render HTML, however, when the page is requested with query string parameters, instead of just doing standard rendering, it will use Response.Clear() and Response.End() and in between of those two commands output JSON version of data based on the query string parameters. Also on the first rendering of the page, it will also output JavaScript template using reflections to read names of the variables from the control's template area.
This method works great, all I have to do, is drop my control on the page, data bind it, and it works as a true AJAX grid that supports pagination, sorting and filtering. However it does have limitation. In the control's template you can only specify variables, not expressions. Otherwise reflections can't convert it to a JavaScript variable. But I can live with that.
Other possibilities that I considered is a separate web-service that takes a type of the page as parameter and uses reflection to get data bound object as well as create template for the grid. I also though about writting my own version of update panel, that would not use view state and only send in part of the page.
In my ASP.NET WebForms application, I have a WebForm that contains an UpdatePanel and multiple views used for a wizard like interface.
At the end of the wizard, the user has an option of moving to another page by clicking a button. This new web page needs about 5 values from controls in the previous page.
What is the simplest way to do this? (Edit: ONLY using an HTTP POST with data - this is a requirement as I would use database/session otherwise)
I tried using cross-page posting with no luck, possibly because of my update panel and multiple views?
I tried using Server.Transfer, but this also breaks because of the update panel.
Important:
Data has to be sent via HTTP POST - The data can't be stored anywhere
The scenario can't be changed. I can't put everything on the same page
The simplest way to do this is by putting those values in the session object.
You could make a class that describes the data that you need to display on the redirected page. Instatiate a new instance of that at the time the user is filling out the wizard data, populate the new classes' object with the information you need, then add it to the session in the button_Click event before page redirection. On the page you are redirected to, grab the Session object, put it into a variable and extract the data you need.
I recommend you combine all the relevant pages into one; hiding panels that are not in play. ASP.NET will maintain the values of all the controls for you from post to post. The Viewstate was designed for sceneries like you describe. To keep to Viewstate size to a minimum, make sure you fill lookup values for drop-down controls in their "Init" methods.
You don't want to use the session state. The last thing you want is for the users to loose their data from previous pages because they took too long to answer.
If they're moving to another page in the solution, you have a few options.
ViewState - The ViewState is sent with the page delivery. It resides in the HTML, but is encrypted so no one can see the information. Depending on the size of the information, your page size could get rather large.
Session - This puts the information client-side via cookies.
Query String - Using the URI. This should only be used if it's non-sensitive information and if you don't want a user to be able to link back to the same action again.