problem with array lists

[Ranmini]

Dear prob solver,

i have a problem with array lists. i am using array lists for adding objects. i just want to know, when you are adding an object to an arraylist whats the value u pass to the add method???

eg:
i have a class call vertex and i want to add an object from that class. so to add that object how to i add that to the arraylist??? do i need to pass the string id or pass an instant of the relevant class??? The code is below

vertex v;
string source_id

arraylist a = new arraylist();
a.add(source_id??) or a.add(v)??? what is correct?

plz send me an answer asap... cz its for my final year project that i need to submit on next wek.. thnx aloot,,,,,,,,
Ran

[nateraaaa]

Dear prob solver,

i have a problem with array lists. i am using array lists for adding objects. i just want to know, when you are adding an object to an arraylist whats the value u pass to the add method???

eg:
i have a class call vertex and i want to add an object from that class. so to add that object how to i add that to the arraylist??? do i need to pass the string id or pass an instant of the relevant class??? The code is below

vertex v;
string source_id

arraylist a = new arraylist();
a.add(source_id??) or a.add(v)??? what is correct?

plz send me an answer asap... cz its for my final year project that i need to submit on next wek.. thnx aloot,,,,,,,,
Ran

An array list can hold an array of any type of object that you would like.

for an array of strings you would do something like this.

string[] arrNames = {"Smith","Jones","Ryan"};
ArrayList a = new ArrayList();
for (int i = 0; i<arrNames.Length; i++)
{
a.Add(arrNames[i].Trim());
}

if you had an array of vertexes try something like this

object[] arrVertex = {vertex1, vertex2, vertex3};
ArrayList b = new ArrayList();
for(int i = 0; i<arrVertex.Length; i++)
{
b.Add(arrVertex[i]);
}

Give these examples a try and let us know if you encounter any other issues.

Nathan

[Plater]

If you want to add the vertex object you would add an instance of it.

vertex v;
string source_id
 
ArrayList a = new ArrayList();
//a.Add(source_id);
//or 
//a.Add(v);<-this one
//??? what is correct? 
 

You should note that any changes made to v after it was added to the ArrayList will not be reflected in the object stored. So make your changes first and do a .Add() after.

[Ranmini]

Can u plz check the below code and let me know whether its right or wrong???? i have a class called vertex and created an object of that class and those set methods are methods from the vertex class...is this code is correct??? what does that mean actually??? i wanted to know whether the desired operation happens throught this code
thnx aloooot...

ArrayList open_list= new ArrayList();
Vertex ObjvertID = new Vertex();

string[] arrayA= VerticesAdjecnt.ReturnAdjectVertArray(sourceID);
for (int v = 0; v < arrayA.Length; v++)
{
ObjvertID.set_vert_id(arrayA[v]);
ObjvertID.set_parent_node_id(sourceID);
open_list.Add(ObjvertID);

}

[Ranmini]

--------------------------------------------------------------------------------

Can u plz check the below code and let me know whether its right or wrong???? i have a class called vertex and created an object of that class and those set methods are methods from the vertex class...is this code is correct??? what does that mean actually??? i wanted to know whether the desired operation happens throught this code
thnx aloooot...

ArrayList open_list= new ArrayList();
Vertex ObjvertID = new Vertex();

string[] arrayA= VerticesAdjecnt.ReturnAdjectVertArray(sourceID);
for (int v = 0; v < arrayA.Length; v++)
{
ObjvertID.set_vert_id(arrayA[v]);
ObjvertID.set_parent_node_id(sourceID);
open_list.Add(ObjvertID);

}

If you want to add the vertex object you would add an instance of it.

vertex v;
string source_id
 
ArrayList a = new ArrayList();
//a.Add(source_id);
//or 
//a.Add(v);<-this one
//??? what is correct? 
 

You should note that any changes made to v after it was added to the ArrayList will not be reflected in the object stored. So make your changes first and do a .Add() after.

[RoninZA]

ArrayList open_list= new ArrayList();
Vertex ObjvertID = new Vertex();

string[] arrayA= VerticesAdjecnt.ReturnAdjectVertArray(sourceID);
for (int v = 0; v < arrayA.Length; v++)
{
ObjvertID.set_vert_id(arrayA[v]);
ObjvertID.set_parent_node_id(sourceID);
open_list.Add(ObjvertID);

}

This looks like it should work just fine...? Although, you'll have to add a new declaration of your ObjvertID at the start of each loop... otherwise you might be getting funny problems with memory being shared between the objects in the ArrayList. So:

ArrayList open_list= new ArrayList();
Vertex ObjvertID = new Vertex();
 
string[] arrayA= VerticesAdjecnt.ReturnAdjectVertArray(sourceID);
for (int v = 0; v < arrayA.Length; v++) 
{
    ObjvertID = new Vertex();
    ObjvertID.set_vert_id(arrayA[v]);
    ObjvertID.set_parent_node_id(sourceID);
    open_list.Add(ObjvertID);
}