Q: how store in hash table in c#? I want to store array or linked list in hash table EX:
       array [,] m = new array(){"doucument",13.4}; 
       hashtable h = new hashtable();
       h.add(1,m );

please help me how store this array in hashtable,and If I can, how access to element this array?
Error:  A nested array initializer is expected  in line 1   
                     array [,] m = new array(){"doucument",13.4};


A:   var dictionary = new Dictionary<int, object[]>();
  dictionary.Add(1, new object[] {"doucument",13.4});

  var arr = dictionary[1];


A: from your question it wasn't obvious if this is a key-value collection or just values. Just to throw it in there, you should know that with .NET 3.5 and up, you can use a HashSet, example:
HashSet<int> numbers = new HashSet<int>();


A: Just get your syntax errors out of your code and it will work fine:
       using System.Collections;

       Array[,] m = new Array[,]{"document",13.4}; 
       Hashtable h = new Hashtable();
       h.Add(1,m );

Accessing the stored element:
       m = (Array[,])h[1]; 

Of course, personally I would prefer the use of System.Collections.Generic.Dictionary;
