Suggestion for implementation, please

Topics: Algorithms, Data Access, General Topics, SharpMap Project, SharpMap v2.0, Web Controls
May 18, 2008 at 3:41 AM
      I am a beginner here and have started using Sharpmap only from a few weeks ago. I want to do a project which basically should do the following.
1. It is a web based project. I am intending to use VS web developer 2005 Express edition with C#
2. I will have a form where I will get the user data for a particular region (say, his rating about the place) in India (I have India shapefile till district level). The user will fill up this form with his rating. The rough entries would be state, district, taluk (subdivision of a district in India) and value/rating.
3. I will get this and store it in database
4. From data base, I want to keep dynamically updating the Indian map with these user values with gradient thematics. 

    The finest detail the user gives is actually a taluk of a particular district. So, our approximation starts here (that is, places of interest further down the taluk is lost as they all are averaged to the taluk level). But I have a shape file till district level only. So I thought of doing either of the following.
1. To request shapefile till taluk level from any government sources here. If I get that, the question is, how am I going to update the map? Should I update the database file (the one that accompanies the shapefile) with database (user ratings) I have and then use the database file to do the thematics? Or can I, in any way do thematics directly with database?
2. To get the coordinates of the taluk in the city. In this case, the taluk should definitely fall inside the district. So, getting the minimum envelope of the point (taluk) should give me the district's polygon that engulfs this point. I just draw a small circle (with smooth not-so-clear circumference and filled with colour representing the level of rating) at that point if it lies fully inside the district's polygon. If it comes close to any of the boundary of the polygon such that, drawing the circle, might leak some part of the circle out of the district's boundary, then that boundary cuts the circle so that the no part of the circle leaks out. This is what I have to accomplish (I don not know how to attach any file to this post. If I can, I can easily show that in a diagram)

      Which one would be easier? The first one, getting a map till taluk level is very costly here. The problem with second one is, I do not know any free source where I can give the name of a place (taluk, and smaller points than a district) and get the coordinates. There is one called geonames, that returns coordinates but it does excellent job only at city level. Not further down the city. 
       Please suggest what do you think on 1st or 2nd ways, and explain how they can be accomplished in sharpmap using C# in web developer 2005 Express edition. I do not know ASP. I just rely on my knowledge about C# and a little bit in Sharpmap. I have to decide the design of web page based on how I am going to handle the back end of it with sharpmap! Please help. Expecting your reply. 

Thanks in advance
Parthiban Rajendran