Re: [WebDNA] Dynamic server feedback?
This WebDNA talk-list message is from 2009
It keeps the original formatting.
numero = 103788
interpreted = N
texte = > No loop, that's the javascript (AJAX). Okay, let's say the browser sends a request to a webdna page so webdna does a search. When this happens webdna returns the current results of the search immediately -- but it does not search again automatically in order to update these results ... So in order to update the search results dynamically in the browser, the AJAX Javascript repeats the original request to the server -- perhaps on a timed basis, and apparently over the original connection which is held open by the XMLHTTPRequest object -- and then Javascript displays the new results in the browser "dynamically" so that the page itself does not have to be reloaded. If this is how it works then webdna is still doing a lot of repeated searches! It's just that the Javascript is making these requests automatically, rather than the visitor clicking a link or form button to get the new results manually. ------- I guess a similar effect might be obtained by putting a meta-refresh tag into a webdna template that's loaded into an iframe. This would effectively repeat the request on a timed basis, sort of like the Javascript does via XMLHTTPRequest. Naturally this approach would result in more server overhead because each of these iframe requests would open and close a new connection -- unlike the XMLHTTPRequest which repeats its requests over the original connection. But if the server is fast enough to handle these repeated requests the end result would look the same to the visitor, correct? Sincerely, Ken Grome
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> No loop, that's the javascript (AJAX). Okay, let's say the browser sends a request to a webdna page so webdna does a search. When this happens webdna returns the current results of the search immediately -- but it does not search again automatically in order to update these results ... So in order to update the search results dynamically in the browser, the AJAX Javascript repeats the original request to the server -- perhaps on a timed basis, and apparently over the original connection which is held open by the XMLHTTPRequest object -- and then Javascript displays the new results in the browser "dynamically" so that the page itself does not have to be reloaded. If this is how it works then webdna is still doing a lot of repeated searches! It's just that the Javascript is making these requests automatically, rather than the visitor clicking a link or form button to get the new results manually. ------- I guess a similar effect might be obtained by putting a meta-refresh tag into a webdna template that's loaded into an iframe. This would effectively repeat the request on a timed basis, sort of like the Javascript does via XMLHTTPRequest. Naturally this approach would result in more server overhead because each of these iframe requests would open and close a new connection -- unlike the XMLHTTPRequest which repeats its requests over the original connection. But if the server is fast enough to handle these repeated requests the end result would look the same to the visitor, correct? Sincerely, Ken Grome
Kenneth Grome
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