.net C# web spider script

The application will get the Sale Id to look for from the user and will crawl into the Christies website searching for the given Sale Id. Then it will get the number of lots that are available under that particular sale id with the url to the lots. Later it will crawl into the url of each lot and get the lot details from the Christies website such as

1. Lot Number
2. Sale Date
3. Sale Number
4. Sale Title
5. Sale Location
6. Creator
7. Title
8. Estimate
9. Lot Description
10. Provenance
11. Lot Notes

Once all the details are collected it will save them in a tab delimited text file.

Finally the application will get the Urls of the images of each lot, will download the images and save them locally in a folder with the filename being the SaleNo-LotNumber of the corresponding Lot in a Jpeg format.