An example of writing and working codes C# using lists of lists List<List<int>>

Grasshopper Developer
1

Hello, Guys

i am developing a plugin for sorting length, i am new to c #
I got that in the main class, there is a method that returns a list of lists and in the grasshopper, at the exit from the node, this output outputs null values

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here is an error when the node is working

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this is how this output is described in the class of outputs in the node

pManager.AddIntegerParameter(“Len”, “Len”, “Length”, GH_ParamAccess.list);

this is how this method in the class processes and forms a list of lists

List<List<int>> Length1 = Length.GetLength();

the problem is that in the output it is impossible to display these lists of lists by branches of the grasshopper tree

DA.SetDataList(0, Length);

2

Hi @AlexWer,

For what you are trying to output, you are trying to output a tree.

GH_ParamAccess.tree

and for the conversion:

GH_Structure<GH_Integer> tree = new GH_Structure<GH_Integer>();
for(int i = 0; i < List.Count;i++)
{
    tree.AppendRange(List[i].Select(j=>new GH_Integer(j)), new GH_Path(new int[]{0,i}));
}
DA.SetDataTree(0,tree);
2 Likes
3

christopher.ho Thank you very much for your answer !!!

I kind of did as you wrote, but the development environment gives errors

I made the conclusion from the component

pManager.AddIntegerParameter(“Len”, “Len”, “Length”, GH_ParamAccess.tree);

this is how I did the conversion, but the environment throws errors (((

GH_Structure<GH_Integer> Length = new GH_Structure<GH_Integer>
for(int i = 0; i < List.Count;i++)
{
Length.AppendRange(List[i].Select(j=>new GH_Integer(j)), new GH_Path(new int{0,i}));
}
DA.SetDataTree(0,Length);

4

Typo on my part.
Should be the following:
GH_Structure<GH_Integer> Length = new GH_Structure<GH_Integer>();

1 Like
5

I did this, but he keeps writing errors and how I understood that with lists of lists I’m not so transforming

у меня вот так сейчас

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but the list of lists has already been announced earlier ((

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these are the error codes

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6

the GH_Structure needs to be a new variable.

List is Length

GH_Structure<GH_Integer> Tree= new GH_Structure<GH_Integer>
for(int i = 0; i < Length.Count;i++)
{
    Tree.AppendRange(Length[i].Select(j=>new GH_Integer(j)), new GH_Path(new int{0,i}));
}
DA.SetDataTree(0,Tree);
2 Likes
7

Thank you very much, rays of gratitude, everything worked !!!