How to populate a treeview from a dataset

[kirknew2SQL]

How to populate a treeview from a dataset

I am very new to C#. I need to create a Windows form that will read a SQL table and populate a treeview. I can connect to the DB, create the dataadapter, populate a data set. The problem is how to use the dataset to populate a treeview.

I have looked at a few examples but none use a dataset, or the data structure was different and I could not modify to work with my data or the examples were more than I needed and too complex for a beginner. Can some one suggest a URL, book or show me an example of code that simply takes the data as shown and populates a treeview.

I would really appreciate the help.

Thank you.


I have a SQL Server 2005 table containing this data shown below.

Child Parent depth Hierachy
1 NULL 0 01
2 1 1 01.02
5 2 2 01.02.05
6 2 2 01.02.06
3 1 1 01.03
7 3 2 01.03.07
11 7 3 01.03.07.11
14 11 4 01.03.07.11.14
12 7 3 01.03.07.12
13 7 3 01.03.07.13
8 3 2 01.03.08
9 3 2 01.03.09
4 1 1 01.04
10 4 2 01.04.10
15 NULL 0 15
15 15 1 15.15
16 15 1 15.16
18 16 2 15.16.18
17 15 1 15.17

[vanc]

How to populate a treeview from a dataset

I am very new to C#. I need to create a Windows form that will read a SQL table and populate a treeview. I can connect to the DB, create the dataadapter, populate a data set. The problem is how to use the dataset to populate a treeview.

I have looked at a few examples but none use a dataset, or the data structure was different and I could not modify to work with my data or the examples were more than I needed and too complex for a beginner. Can some one suggest a URL, book or show me an example of code that simply takes the data as shown and populates a treeview.

I would really appreciate the help.

Thank you.


I have a SQL Server 2005 table containing this data shown below.

Child Parent depth Hierachy
1 NULL 0 01
2 1 1 01.02
5 2 2 01.02.05
6 2 2 01.02.06
3 1 1 01.03
7 3 2 01.03.07
11 7 3 01.03.07.11
14 11 4 01.03.07.11.14
12 7 3 01.03.07.12
13 7 3 01.03.07.13
8 3 2 01.03.08
9 3 2 01.03.09
4 1 1 01.04
10 4 2 01.04.10
15 NULL 0 15
15 15 1 15.15
16 15 1 15.16
18 16 2 15.16.18
17 15 1 15.17

You can read through data to manually add nodes into treeview one by one. You can use datareader to do this.
e.g. if(reader.HasRow)
while(reader.Read())
treeview.nodes.add(reader["field name"].ToString());
cheers.

[kirknew2SQL]

[quote=vanc]You can read through data to manually add nodes into treeview one by one. You can use datareader to do this.
e.g. if(reader.HasRow)
while(reader.Read())
treeview.nodes.add(reader["field name"].ToString());
cheers.[/QUOTE


If I use that technique if a branch has say 4 levels but the second level node has children how do I get back to that node to populate it’s children? Like in the example:
Child Parent
1..... null
2..... 1
3..... 2
4..... 3
5..... 2
6..... 5

If I simply add nodes one at a time from the data reader, when I get to 5 I am lost. Have I missed something?

[vanc]

[quote=kirknew2SQL]

You can read through data to manually add nodes into treeview one by one. You can use datareader to do this.
e.g. if(reader.HasRow)
while(reader.Read())
treeview.nodes.add(reader["field name"].ToString());
cheers.[/QUOTE


If I use that technique if a branch has say 4 levels but the second level node has children how do I get back to that node to populate it’s children? Like in the example:
Child Parent
1..... null
2..... 1
3..... 2
4..... 3
5..... 2
6..... 5

If I simply add nodes one at a time from the data reader, when I get to 5 I am lost. Have I missed something?

Since every node has its value, you can check its value from the root node to the end node and stop and the node with the appropriate value to add child node to it.