Programming Forums > Application Development > Visual Basic

chepfaust · Feb 19th, 2005, 2:38 PM

i can't find any information on how to do this whatsoever anywhere on the internets.

a user selects multiple(!) not necessarily consecutive items from a dirlistbox and clicks a button, which ideally would write the contents of each selected line to a text file.

now, i can do dirlistbox.text and dirlistbox.listindex for reading a single selection, but each command only reads the last selection entered, and even if i manually set

(Toggle Plain Text)

dirlistbox.selected(dirlistbox.listindex) = false
'sets whatever was last selected to false

the computer doesn't remember what was selected before that, so there is no more information the program will read from the dirlistbox.

any ideas?

samurai · Feb 22nd, 2005, 12:47 AM

try to use an array...put the selections in the array.

and try to check first how many items the user has selected.

hope this helps

Pizentios · Feb 22nd, 2005, 9:17 AM

Quote:

A ListBox control displays a list of items from which the user can select one or more. If the number of items exceeds the number that can be displayed, a scroll bar is automatically added to the ListBox control.

If no item is selected, the ListIndex property value is -1. The first item in the list is ListIndex 0, and the value of the ListCount property is always one more than the largest ListIndex value.

To add or delete items in a ListBox control, use the AddItem or RemoveItem method. Set the List, ListCount, and ListIndex properties to enable a user to access items in the ListBox. Alternatively, you can add items to the list by using the List property at design time.

That's from the msdn libaray. And you said there was nothing on the web about list boxes :-)

Anyways, to do what you want (or at least what i think you want to do), you would use the Selected property of the Listbox and a loop of your choosing. He's some more info about the selected property.

Quote:

Returns or sets the selection status of an item in a FileListBox or ListBox control. This property is an array of Boolean values with the same number of items as the List property. Not available at design time.

So now i'll show you in code.

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      for x=0 to (myListBox.ListCount - 1) Step 1
      		if (myListBox.Selected == true) then
 			'do something with the item, like put it an array for later 
 			'use, or you could even write it to the text file from here.
    		  end if
      Next x

anyways, if i read your post right, that sould be what you need. you could use a do while loop or any other loop you want, but i jus tplain like for loops :-)

chepfaust · Feb 27th, 2005, 1:45 AM

Quote:

Originally Posted by Pizentios

That's from the msdn libaray. And you said there was nothing on the web about list boxes :-)

Anyways, to do what you want (or at least what i think you want to do), you would use the Selected property of the Listbox and a loop of your choosing. He's some more info about the selected property.

So now i'll show you in code.

(Toggle Plain Text)

      for x=0 to (myListBox.ListCount - 1) Step 1
      		if (myListBox.Selected == true) then
 			'do something with the item, like put it an array for later 
 			'use, or you could even write it to the text file from here.
    		  end if
      Next x

anyways, if i read your post right, that sould be what you need. you could use a do while loop or any other loop you want, but i jus tplain like for loops :-)

well initially i DID look at the msdn library, but the part where it says "If no item is selected, the ListIndex property value is -1" was really screwing up my loops and causing my computer to hang. it took me a long while but i later discovered that if i selected one item and then de-selected it, the listindex value would go to 0, not -1, so the program would keep looping until it reached a value (-1) it would never possibly reach :\

i have no experience with using arrays but it sounds promising so i'll have to read up on that. thanks for the suggestions though.

edit:

OH MY GOD if i had known about arrays and their capabilities earlier in this project, it would have saved me many hours' worth of toil and made my program run more efficiently to boot.

i'm starting over now. lol

Feb 19th, 2005, 2:38 PM	#1
chepfaust Programmer Join Date: Feb 2005 Posts: 62 Rep Power: 4	reading from a listbox i can't find any information on how to do this whatsoever anywhere on the internets. a user selects multiple(!) not necessarily consecutive items from a dirlistbox and clicks a button, which ideally would write the contents of each selected line to a text file. now, i can do dirlistbox.text and dirlistbox.listindex for reading a single selection, but each command only reads the last selection entered, and even if i manually set (Toggle Plain Text) dirlistbox.selected(dirlistbox.listindex) = false 'sets whatever was last selected to false dirlistbox.selected(dirlistbox.listindex) = false 'sets whatever was last selected to false the computer doesn't remember what was selected before that, so there is no more information the program will read from the dirlistbox. any ideas? Last edited by chepfaust; Feb 19th, 2005 at 2:45 PM.

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Feb 22nd, 2005, 12:47 AM	#2
samurai Newbie Join Date: Feb 2005 Posts: 4 Rep Power: 0	try to use an array...put the selections in the array. and try to check first how many items the user has selected. hope this helps

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Programming Forums > Application Development > Visual Basic

reading from a listbox