best deal with value pairs that contain duplicates

[rno]

Hi,

I'm sorry if I'm asking for the obvious - my head is spinning a bit
trying to learn this c# stuff.

I have a list of paired values in the form of:

stringA, string1
stringB, string2
stringC, string1
stringC, string3
stringD, string2
etc..

I need to store these value pairs into some kind of collection. Since
I do not have unique 'keys', I cannot use a Dictionary or SortedList.
The combination of -say- stringA+string1 *will* be unique. (if
case-sensitive). That could serve as a key, but then I need to store 2
values.

My goal is to query the collection for stringA, and find all
associated strings 1, 2, etc.

My current idea is to create a simple 3-field table in a dataset.
Another way -since this is for a Form app- could be to use an
invisible ListView (not too keen on that). Either way, I have a
feeling I might be overly complicating things.

I'd appreciate some general advice on how to best deal with this.

tia
arno

 

[Arne Vajhøj]

Hi,

I'm sorry if I'm asking for the obvious - my head is spinning a bit
trying to learn this c# stuff.

I have a list of paired values in the form of:

stringA, string1
stringB, string2
stringC, string1
stringC, string3
stringD, string2
etc..

I need to store these value pairs into some kind of collection. Since
I do not have unique 'keys', I cannot use a Dictionary or SortedList.
The combination of -say- stringA+string1 *will* be unique. (if
case-sensitive). That could serve as a key, but then I need to store 2
values.

My goal is to query the collection for stringA, and find all
associated strings 1, 2, etc.

My current idea is to create a simple 3-field table in a dataset.
Another way -since this is for a Form app- could be to use an
invisible ListView (not too keen on that). Either way, I have a
feeling I might be overly complicating things.

I'd appreciate some general advice on how to best deal with this.

Based on how you intend to use it then a:

Dictionary<string,List<string>>

looks obvious to me.

Arne

 

[RayLopez99]

Based on how you intend to use it then a:

Dictionary<string,List<string>>

looks obvious to me.

Arne

Or hash table, which allows for collisions.

 

[rno]

(e-mail address removed)>, (e-mail address removed)
says...>

Or hash table, which allows for collisions.

Tx guys. I also found the KeyValuePair struct, which might come in
handy.

arno

 

[Göran Andersson]

Or hash table, which allows for collisions.

A HashTable doesn't allow for collisions. The key has to be unique, the
hash code of the key is only used for performance, not instead of the key.

 

[Arne Vajhøj]

Or hash table, which allows for collisions.

Hashtable (or if .NET version >= 2.0 Dictionary<string,String>)
can not have multiple values for the same key.

Arne

 

[RayLopez99]

Tx guys. I also found the KeyValuePair struct, which might come in
handy.

You are welcome. I think KeyValuePair is simply a fancy name for
Dictionary, at least that's how I interpret it.

RL

 

[Jeff Johnson]

You are welcome. I think KeyValuePair is simply a fancy name for
Dictionary, at least that's how I interpret it.

Close. A KeyValuePair<K, V> is the generic version of what in pre-generic
..NET was called a DictionaryEntry. They aren't dictionaries themselves,
rather they're what dictionaries contain.