Transferring items from a listbox to a string variable [modified]

[gamer1127]

Hello. I'm having a little problem transferring all the items in the listbox to a string variable. All the items in the listbox are also string type so i don't have any problems about data types. I tried to use array of string type variable but when i transfer them using a for..loop statement it gets a run-time error that the index was out of bounds. How will I resolve that? How can i store all the items into a variable without selecting them? I used the listbox as a control for outputs. this is the code:

for (int a = 0; a < lstBoxRequests.Items.Count; a++)
{
string[] passedRequests = new string[a];

                passedRequests\[a\] = Convert.ToString(lstBoxRequests.Items\[a\]);

                MessageBox.Show(passedRequests\[a\]);
            }

modified on Friday, November 6, 2009 6:41 AM

[Covean]

Try this:

string[] passedRequests = new string[lstBoxRequests.Items.Count];
for (int a = 0; a < lstBoxRequests.Items.Count; a++)
{

                passedRequests\[a\] = Convert.ToString(lstBoxRequests.Items\[a\]);

                MessageBox.Show(passedRequests\[a\]);
            }

Greetings Covean

[Lost User]

How manu elements are there in your array? And how many elements would the loop go through? If your array holds 10 items, then a for-next loop will go from either 1 to 10 or from 0 to 9. Your loop goes 11 times, starting at passedRequest[0] and moving on to passedRequst[10], generating an "index out of bounds". That means that the number between the [] is smaller or larger then the number of items in the array :)

for (int a = 0; a < lstBoxRequests.Items.Count -1; a++)

Next item is that you're reinitializing the array on each loop. That means that the entire Array is created anew, with a new maximum-upperbound of "a". You'd prolly want a maximum number in the array that corresponds to the number of items in the combobox. That would come to something like this;

int itemCount = lstBoxRequests.Items.Count -1;
string[] passedRequests = new string[itemCount];
for (int a = 0; a < itemCount; a++)
{
passedRequests[a] = Convert.ToString(lstBoxRequests.Items[a]);

There are easier ways to enumerate through the items, but I'll leave that to the next poster :)

I are Troll :suss:

[V 0]

I think you'll miss one item with this code.

Eddy Vluggen wrote:

for (int a = 0; a < lstBoxRequests.Items.Count -1; a++)

or do this:

for (int a = 0; a <= lstBoxRequests.Items.Count -1; a++)

or this:

for (int a = 0; a < lstBoxRequests.Items.Count; a++)

V.
Stop smoking so you can: Enjoy longer the money you save. Moviereview Archive

[Covean]

for (int a = 0; a < lstBoxRequests.Items.Count; a++)

Is right, your loop:

for (int a = 0; a < lstBoxRequests.Items.Count - 1; a++)

is wrong it leaves one item alone! General: for(int loop=0; loop < count; loop++) or for(int loop=0; loop <= count -1; loop++)! His problem was the following:

for (int a = 0; a < lstBoxRequests.Items.Count; a++)
{
string[] passedRequests = new string[a];

                passedRequests\[a\] = Convert.ToString(lstBoxRequests.Items\[a\]);   <---- this causes the out of array, because passedRequests.length = a but passedRequests\[a\] is wrong !!!

                MessageBox.Show(passedRequests\[a\]);
            }

Edit: Second problem was the creation of the string array in the loop.

Greetings Covean

[Lost User]

Covean wrote:

or (int a = 0; a < lstBoxRequests.Items.Count - 1; a++) is wrong it leaves one item alone!

You're right, I was wrong. I've been looking at these too much;

for(int x = 0; x <= bla.Count - 1; x++)

Notice that the check has an equals-sign. The current project that I'm working has both styles mixed throughout the code. In VB6 :)

I are Troll :suss:

[V 0]

Eddy Vluggen wrote:

In VB6

that explains it :-D

V.
Stop smoking so you can: Enjoy longer the money you save. Moviereview Archive