Thank you very much, Shaun. I Googled a lot and all i found is bunch of application that converts shapefiles to kml. But in my requirement i have to write a code(flex class) that can convert a .shp file and .dbf to kml file.I have already written a flex code that displays the converted kml file on google map.
On Jul 19, 8:21 pm, Shaun <[email protected]> wrote: > Hi Kanak, > As others have posted you'll get a benefit in performance of your > application if you have some way to process the shapefiles into kml in > advance of sending all the data to the client. Basically the way the data > flow goes is this: > > Sorry if I get too basic not meaning to be demeaning in any way just trying > to give a clear explanation that hopefully anyone can understand. > > Someone goes to your websitehttp://www.shaunhusain.com, that persons > computer is considered the client machine and it sends a message to the > server which is a computer owned and maintained by your hosting provider or > it could be you if you have your own server you maintain. > > Anyways, point being that machine is considered the "middle-layer" and may > point to databases either on the server itself or on other servers(or just > use files stored on the server, or run independently of any data, though > this last case is rare). The middle layer is just an Apache or other HTTP > server or a "web application server/J2EE server" which is a big complicated > way of saying it runs java applications that are persistent, that is they > can stay in memory and running between requests from the client, whereas > HTTP servers like apache or IIS rest in between requests. There's lots of > different servers out therehttp://greatstatistics.com/I personally run > Apache though I'm not experienced enough with other servers to make a fair > comparisonhttp://www.apache.org. > > Okay too much detail, overall though request goes from the client to the > server, the server at this point has a chance to do some work before sending > back a reply, this work would be coded up in Java, PHP, Python, Perl, C#, or > some other technology for which a server module or a server has been > built... generally from what I've seen, it's one of the first two as they > can be obtained pretty much free and there's large communities of users and > libraries of code already in existence. This would be considered the > middle-layer, this middle-layer could in turn make a request to a database, > more formally most modern databases are called Relational Database > Management Systems RDBMSs for short, these would be MySQL, Postgres, SQLite, > MSSQL, Teradata, Informatica, etc. All of these share Structured Query > Language (SQL) which is basically like a language for asking the database to > fetch and aggregate certain pieces of information or to create table > structure or insert/update/delete data, there are variances within each > RBDMSs interpretation of SQL but for the basic problems the SQL is the same. > > Why does all this matter? Well if you leave converting from a Shapefile to > a KML file up to the client-machine then every single persons client > computer has to do the processing after they get the code from your server > and if people don't have the latest and greatest hardware it may equal an > unreasonable performance hit for your end users. So the other options based > on how it's all working are, 1 to have the middle-layer do the processing, > so when someone makes the request the server takes a small performance hit > to do the conversion, the third option is to do the conversion in advance > and store the results, the stored results would be considered the "back-end" > in this case, generally this would be stored in a database of some sort but > just storing files in some cases is good enough. Below is a tool I found by > googling "shapefile to kml" without the quotes, it'a windows program that > was written using visual basic that supposedly will do the conversion for > you (if you run another OS just make the search more specific you'll likely > find something). I think the best option is to just manually do the > conversion unless you have 100s or 1000s or more of shapefiles in which case > I would write some sort of script/mini application to batch the work (in > this case I think Python or some other scripting language could be helpful). > Then you can take the KML and use the KML parser that's already out there > to have it generate the appropriate overlay. > > http://arcscripts.esri.com/details.asp?dbid=14273 > > http://gmaps-utility-library-flash.googlecode.com/svn/trunk/examples/... > > Also there's prepackaged versions of Apache/PHP/MySQL that can be downloaded > for any operating system the names are > > MAMP for Mac > LAMP for linux > WAMP for windows > > this isn't production ready, but is good enough to develop against, when you > put the site live you're likely to be using a web hosting company anyhow. > You can also download Tomcat to act as a container application for your > web-applications if you're interested in Java. All of these servers work > pretty well with Flex also, it's got some integration tools that will allow > you to quickly generate forms or data-grids based off of a database > definition and eliminates a ton of the "middle-layer" work filling in the > PHP or Java files and creating all the hooks to use requests to the database > to select or modify any table in it. > > Good luck, > Shaun -- You received this message because you are subscribed to the Google Groups "Google Maps API For Flash" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/google-maps-api-for-flash?hl=en.
