General question about javascript (REST vs. SOAP)

I'm calling a webservice currently from the backend. However, the page is taking a while to load and I'm starting to wonder, will the page load faster (in a perceived way) if I use javasc开发者_开发技巧ript to load the data instead of the backend?

Basically will using a REST service to load the data on the client side make the page load seem faster than loading the data on the backend with a SOAP call? Does page_load fire first or the javascript calls?

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In terms of the difference between calling a SOAP service on the backend vs. calling a REST/JSON service on the front end - your page load times may be percieved as faster if you let the frame of the page load, and display a "spinner" when you load the data from a REST service.

Your question is a bit ambiguous since it's not clear that's what you're asking.

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Well, REST vs. SOAP isn't really a comparison anyone can make in terms of speed/performance on a website. REST refers to a conceptual semantic model of how to make calls to a service. SOAP, on the other hand, refers to both the semantics of the call, as well as the data format. REST, by comparison, says nothing about the data format (although JSON is typically assumed - but nothing about REST precludes XML or any other data format).

JSON vs. SOAP, however, is a different story.

JSON responses will be easier / faster to parse on the client side than SOAP messages will (assuming you're using standard javascript stuff which works cross-platform, and no fancy plugins).

Load time? SOAP is a LOT more verbose than JSON, and requires additional characters to transmit the same values... so maybe a small delay due to the relative sizes of the messages being sent.

Processing time on the client side? JSON definitely has the edge.

Ease of use on the client? JSON - hands down.

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I see this question not as much as a comparison between REST and SOAP, but rather a question about where the service should be called - backend or frontend. Backend code always executes first, before any frontend code, by definition - it just sits on the server, and runs before the response is returned. The javascript runs after the response is returned and the page is loaded.

Steve gave a very good overview, but it doesn't talk at all about backend v.s frontend. Generally speaking there will be no difference in performance or at least no difference that can be predicted. It all depends on the server condifuration and client computers (where the Javascript executes).

The difference (as Steve also mentioned) is in perceived performance. Here, I would always recommend that you call services from the frontend. There are a couple of reasons:

1. You can display a visual indicator before you call the service to inform the user of the lengthy operation
2. You can do a partial update of the UI on each next call to the service. If you call the service in the backend, you would have to essentially do a postback (go through the whole lifecycle of your ASP.NET page). This is slow and not visually appealing.

Actually if you are calling a service from the backend I see no point in having a service at all (assuming it only returns data to bind to the UI). You can just use the old Webforms way to construct the UI and return the response directly in your ASP.NET page.

As a conclusion - many of the benefits of web services come when you call them from client script.

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Without looking in your code i cant realy say whats wrong/ why is site loading not fast enough. REST and SOAP are definied standarts for comuniation between client and server. I prefer REST over SOAP.

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The direct answer for your question is: Page_Load event will load before your Javascript background calls. I recommend using javascript with background loading when your page has several web controls that load too much data, draw elements or doing heavy calculations that take much time and affect the user experience and application performance. You need to give the user the ability to load the page and seeing the progress of each element loading (so that he don't get bored while browsing). REST calls with JSON is recommended for this case.