CODEWITHSUNDEEP
c#asp.netdrop-down-menu
Kadir
Kadir

Reputation: 3224

Dropdownlist and categories subcategories

I was try to load unlimited categories to dropdownlist but I failed.

**Categories**
ID, MainCategoryID, CatName, Description, dateCreated, isActive
1, 0, Cars, "blabla", 26.06.2012, True
2, 1, Ferrari, "blabla", 26.06.2012, True
3, 1, Lamborgini, "blabla", 26.06.2012, True
4, 2, F-40, "blabla", 26.06.2012, True
5, 2, F-50, "blabla", 26.06.2012, True
6, 0, Motorbikes, "blabla", 26.06.2012, True

- MainCategory
  -- SubCategory1
  -- SubCategory2
     -- SubSubCategory1
- MainCategory
- MainCategory
  -- SubCategory3
     -- SubSub .. so on

Is it possible to do that in dropdownlist control?

Upvotes: 0

Views: 1390

Answers (1)

nunespascal
nunespascal

Reputation: 17724

It is definitely possible. You only need a little recursion. Can be done in your sql query itself.

If you are using sql server you can achieve recursion using common table expressions

If you are confused about this, put a comment and I will write the query to show you.

WITH cat(ord,lev, id, mainID, catName) AS
(
    SELECT ID*POWER(100, 3) AS ord, 1 AS lev, ID, MainCategoryID,CatName FROM test WHERE MainCategoryID =0
    UNION ALL 
    SELECT cat.ord + test.ID * POWER(100, 3-lev) AS ord,lev+1 AS lev, test.ID, test.MainCategoryID, test.CatName AS CatName FROM test INNER JOIN cat ON test.MainCategoryID = cat.ID
)
SELECT * FROM cat ORDER BY ord

lev column gives you the level of the row. ord column is used to order your items. This example allows for upto 100 ids and 3 levels.

Though I have ordered the data here, this is best done in c#, using recursion there.

Upvotes: 1

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