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plurals

POobject reference not set to an instance of an object, cannot figure out why
primarykey
Id
10064808
data
AcceptedAnswerId
10064980
AnswerCount
3
ClosedDate
CommentCount
5
CommunityOwnedDate
CreationDate
2012-04-08T17:28:17.787
FavoriteCount
0
LastActivityDate
2012-04-08T17:56:17.333
LastEditDate
2012-04-08T17:43:14.053
LastEditorUserId
76337
OwnerUserId
1320551
ParentId
0
PostTypeId
1
Score
0
ViewCount
923
LastEditorDisplayName
text
Body
I quite new to c# and asp.net so plz tell me if i give you to little info for my question. When a user is logging in I create an instance of my User object, calling my getcategories method and the redirect then user to another page. Like this: <pre><code>if (dt.Rows.Count > 0){ user apa = new user(); apa.namn = dt.Rows[0]["FirstName"].ToString() + " " + dt.Rows[0]["LastName"].ToString(); apa.mail = dt.Rows[0]["Email"].ToString(); apa.id = dt.Rows[0]["ID"].ToString(); apa.firstname = dt.Rows[0]["FirstName"].ToString(); apa.lastnamn = dt.Rows[0]["LastName"].ToString(); apa.password = dt.Rows[0]["Password"].ToString(); Session["user"] = apa; apa.getcategories(); Response.Redirect("visainlagg.aspx"); } </code></pre> The problem is that I get "object reference not set to an instance of an object"-error on "kategorier[i].Name = dt.Rows[i]["Name"].ToString();" (the first thing that happens in my for loop in User class). I do not understand why :( This is how the User class looks like: <pre><code>public string namn; public string mail; public string id; public string firstname; public string lastname; public string password; public string constr = "secret"; public Post[] poster; public anvcateg[] kategorier; public int antalKategorier; public void getcategories() { SqlConnection conn = new SqlConnection(); conn.ConnectionString = constr; SqlCommand com = new SqlCommand(); com.Connection = conn; com.CommandText = "SELECT * FROM Category WHERE Author= '" + id + "'"; SqlDataAdapter adp = new SqlDataAdapter(); adp.SelectCommand = com; DataTable dt = new DataTable(); adp.Fill(dt); antalKategorier = dt.Rows.Count; kategorier = new anvcateg[dt.Rows.Count]; for (int i = 0; i < dt.Rows.Count; i++) { kategorier[i].Name = dt.Rows[i]["Name"].ToString(); kategorier[i].ID = dt.Rows[i]["ID"].ToString(); kategorier[i].Description = dt.Rows[i]["Description"].ToString(); kategorier[i].Author = dt.Rows[i]["Author"].ToString(); } } </code></pre> the anvcateg class that getcategories() is using looks like this: <pre><code>public class anvcateg { public string ID; public string Name; public string Description; public string Author; </code></pre>
Tags
<c#><asp.net><object>
Title
object reference not set to an instance of an object, cannot figure out why
singulars
PostAcceptedAnswerId
1. PO
 singulars
 PostTypePostTypeId
 PTAnswer
PostParentId
1. This table or related slice is empty.
PostTypePostTypeId
1. PTQuestion
UserLastEditorUserId
1. USJohn Saunders
UserOwnerUserId
1. UStobbe
plurals
PostLinksPostIdRelatedPostId
1. PL
 singulars
 LinkTypeLinkTypeId
 LTLinked
PostLinksRelatedPostIdPostId
1. This table or related slice is empty.
PostsAcceptedAnswerId
1. This table or related slice is empty.
PostsParentIdCreationDate
1. PO
 singulars
 PostTypePostTypeId
 PTAnswer
2. PO
 singulars
 PostTypePostTypeId
 PTAnswer
3. PO
 singulars
 PostTypePostTypeId
 PTAnswer
VotesPostIdCreationDate
1. VO
 singulars
 PostPostId
 POobject reference not set to an instance of an object, cannot figure out why
 UserUserId
 This table or related slice is empty.
 VoteTypeVoteTypeId
 VTUpMod
2. VO
 singulars
 PostPostId
 POobject reference not set to an instance of an object, cannot figure out why
 UserUserId
 This table or related slice is empty.
 VoteTypeVoteTypeId
 VTDownMod
CommentsPostId

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