Question Is there a better way to return Int or Null

Hi guys,

I need to get an index of an object from the list so I can use it in other functions.
What I did seems overcomplicated
Is there a more cleaner way to return int or nothing ?

Thank you

Code (CSharp):

1. // Select node
2.     private int? SelectNodeIndex(Vector3 position)
3.     {
4.         if (polygons != null)
5.         {
6.             foreach (var polygon in polygons.Items)
7.             {
8.                 for (int i = 0; i < polygon.Nodes.Count; i++)
9.                 {
10.                     if (IsSamePosition(TouchWorldPosition(position), polygon.Nodes[i].Position))
11.                     {
12.                         isSelected = true;
13.                         return i;
14.                     }
15.                     else
16.                     {
17.                         return null;
18.                     }
19.                 }
20.             }
21.  
22.             return null;
23.         }
24.         else
25.         {
26.             return null;
27.         }
28.     }

 

To many returns in my code looks messy

 

First of all avoid too deep nesting. When you have a method you can use early-exit guard clauses at the beginning. This avoids unnecessary nesting. Further more your else statement inside your for loop doesn't make much sense. After the first loop iteration you return no matter what. I guess you only want to return null when no element matches the condition.

Something like this:

Code (CSharp):

1.     private int? SelectNodeIndex(Vector3 position)
2.     {
3.         if (polygons == null)
4.             return null;
5.         foreach (var polygon in polygons.Items)
6.         {
7.             for (int i = 0; i < polygon.Nodes.Count; i++)
8.             {
9.                 if (IsSamePosition(TouchWorldPosition(position), polygon.Nodes[i].Position))
10.                 {
11.                     isSelected = true;
12.                     return i;
13.                 }
14.             }
15.         }
16.         return null;
17.     }

Though I'm not sure how you want to use that returned index. You iterate through all your "polyons" and the index may match a node in "some" of the polygons. You don't return which one. Of course we don't know what those "Nodes" inside a polygon actually are. But just returning the index into the Nodes array of "some" polygon may not be that helpful.

However those may be logical issues that can only be solved by yourself.

 

Hi @Bunny83

Thank you for your advise. The reason for this function is to be able to find a node index, so I can move it later.
I currently have this function, I though to brake it into two will make sense.
So one to select an object and second to move it?

But I just discovered that I will need to get a polygon index as well. As I may have multiple polygons.

Please let me know what you think as it will help me a lot.

Thanks again

Code (CSharp):

1.   // Move node
2.     public void MoveNode(Vector3 position)
3.     {
4.         if (polygons != null)
5.         {
6.             foreach (var polygon in polygons.Items)
7.             {
8.                 for (int i = 0; i < polygon.Nodes.Count; i++)
9.                 {
10.                     if (IsSamePosition(TouchWorldPosition(position), polygon.Nodes[i].Position))
11.                     {
12.                         isSelected = true;
13.                         selectedNodeIndex = i;
14.                     }
15.                 }
16.  
17.                 if (isSelected)
18.                 {
19.                     Debug.Log("Moving node.");
20.                     polygon.Nodes[selectedNodeIndex].Position = Vector3.MoveTowards(polygon.Nodes[selectedNodeIndex].Position, TouchWorldPosition(position), 100f);
21.                 }
22.             }
23.  
24.         }
25.  
26.     }

 

Each polygon has a collection of nodes and edges. Each node is basically Vector3 position with some helper functions.
So Polygons and Nodes are Runtime collection which I can change at runtime.
I use these runtime collections to dynamically update mesh generation