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Question about casting

Hi,

I have a Hashtable, key is string and value is ArrayList. The problem is I
cannot cast the value from object to ArrayList.
like this:

Hashtable ht = new Hashtable();
ArrayList al = new ArrayList();
al.Add("test");
ht.Add("key1", al);

ArrayList al1 = (ArrayList)(Has htable["key1"]; // .

The result of al1 is a ArrayList which has 1 item. al1[0] was a string value
"system.collect ions.arraylist" , and there is no cast exception throwed.
What's the problem?

Thanks!
Andy
Mar 20 '06 #1
3 1231
You are mistaken.
You have not done what you say that you have (Your lookup line wouldn't
compile)
Check again or post full code.

"Andy Chen" <pp****@hotmail .com> wrote in message
news:up******** ******@TK2MSFTN GP11.phx.gbl...
Hi,

I have a Hashtable, key is string and value is ArrayList. The problem is I
cannot cast the value from object to ArrayList.
like this:

Hashtable ht = new Hashtable();
ArrayList al = new ArrayList();
al.Add("test");
ht.Add("key1", al);

ArrayList al1 = (ArrayList)(Has htable["key1"]; // .

The result of al1 is a ArrayList which has 1 item. al1[0] was a string
value "system.collect ions.arraylist" , and there is no cast exception
throwed.
What's the problem?

Thanks!
Andy

Mar 20 '06 #2
Andy,

The result should be an array list with 1 element - string with text "test".
If you don't get that you do something wrong.

Can you post compilable (preferable console) sample that demonstrates your
problem.

--

Stoitcho Goutsev (100)

"Andy Chen" <pp****@hotmail .com> wrote in message
news:up******** ******@TK2MSFTN GP11.phx.gbl...
Hi,

I have a Hashtable, key is string and value is ArrayList. The problem is I
cannot cast the value from object to ArrayList.
like this:

Hashtable ht = new Hashtable();
ArrayList al = new ArrayList();
al.Add("test");
ht.Add("key1", al);

ArrayList al1 = (ArrayList)(Has htable["key1"]; // .

The result of al1 is a ArrayList which has 1 item. al1[0] was a string
value "system.collect ions.arraylist" , and there is no cast exception
throwed.
What's the problem?

Thanks!
Andy

Mar 20 '06 #3
Thanks for your respnoses!
I made mistake at somewhere else, the casting is OK.

I apologize for this trash post.

"Stoitcho Goutsev (100)" <10*@100.com> wrote in message
news:eK******** *****@TK2MSFTNG P12.phx.gbl...
Andy,

The result should be an array list with 1 element - string with text
"test". If you don't get that you do something wrong.

Can you post compilable (preferable console) sample that demonstrates your
problem.

--

Stoitcho Goutsev (100)

"Andy Chen" <pp****@hotmail .com> wrote in message
news:up******** ******@TK2MSFTN GP11.phx.gbl...
Hi,

I have a Hashtable, key is string and value is ArrayList. The problem is
I cannot cast the value from object to ArrayList.
like this:

Hashtable ht = new Hashtable();
ArrayList al = new ArrayList();
al.Add("test");
ht.Add("key1", al);

ArrayList al1 = (ArrayList)(Has htable["key1"]; // .

The result of al1 is a ArrayList which has 1 item. al1[0] was a string
value "system.collect ions.arraylist" , and there is no cast exception
throwed.
What's the problem?

Thanks!
Andy



Mar 23 '06 #4

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