Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people, just like you, are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
Solved

Two dimensional array of textboxes

Posted on 2006-06-27
7
330 Views
Last Modified: 2008-02-01
Hi,

I want to have a 2dimensional array of textboxes ...
I wrote this code..( learning C# so pls be patient)


                                                for (int x = 0; x<8; x++)
                  for (int i = 0; i<8; i++)
                  {
                         
                        System.Windows.Forms.TextBox[][]tb ;
----------------->            tb[x][i]=  new System.Windows.Forms.TextBox();
                        tb[x][i].Text = "";
                        tb[x][i].TabIndex = i;
                        tb[x][i].Size = new System.Drawing.Size(20,20);
                        tb[x][i].Location = new System.Drawing.Point(x*70, i*25);
                        tb[x][i].Text = i.ToString();
                        this.Controls.Add(tb[x][i]);
                  }

ERROR: Use of unassigned local variable 'tb'

How do i solve this
0
Comment
Question by:pai_prasad
  • 4
  • 2
7 Comments
 
LVL 13

Expert Comment

by:devsolns
ID: 16994675
System.Windows.Forms.TextBox[][]tb ;   <---just a reference to nothing.

need to make,
int size = 50;
System.Windows.Forms.TextBox[][]tb  = new System.Windows.Forms.TextBox[size][];
0
 
LVL 13

Expert Comment

by:devsolns
ID: 16994703

Alternatives as well,

                //Framework 1.1
                ArrayList list = new ArrayList();
                list.Add(new System.Windows.Forms.TextBox());

                //Framework 2.0
                System.Collections.Generic.List<System.Windows.Forms.TextBox> = new List<System.Windows.Forms.TextBox>();
                list.Add(new System.Windows.Forms.TextBox());


I would still learn to use arrays though.  They are a critical element in comptuer science.
0
 
LVL 10

Author Comment

by:pai_prasad
ID: 16994713
i tried that ...
System.Windows.Forms.TextBox[][]tb = new TextBox[8][];


it gives error: Object reference not set to an instance of an object. on

tb[x][i].Text = "";
0
Networking for the Cloud Era

Join Microsoft and Riverbed for a discussion and demonstration of enhancements to SteelConnect:
-One-click orchestration and cloud connectivity in Azure environments
-Tight integration of SD-WAN and WAN optimization capabilities
-Scalability and resiliency equal to a data center

 
LVL 13

Expert Comment

by:devsolns
ID: 16994963

see your not using a 2 dimensional array, your using an array of an array

int size = 50;
System.Windows.Forms.TextBox[][]tb  = new System.Windows.Forms.TextBox[size][];

int size2 = 2;
tb[0] = new System.Windows.Forms.TextBox[size2];


2d array looks like System.Windows.Forms.TextBox[,] tb = new System.Windows.Forms.TextBox[,] {{new System.Windows.Forms.TextBox(), new System.Windows.Forms.TextBox()}, {new System.Windows.Forms.TextBox(), new System.Windows.Forms.TextBox()}}

0
 
LVL 5

Accepted Solution

by:
AdGroot earned 500 total points
ID: 16994977
try this

            System.Windows.Forms.TextBox[][] tb = new TextBox[8][];
            for (int x = 0; x < 8; x++)
            {
                tb[x] = new TextBox[8];
                for (int i = 0; i < 8; i++)
                {

                    tb[x][i] = new System.Windows.Forms.TextBox();
                    tb[x][i].Text = "";
                    tb[x][i].TabIndex = i;
                    tb[x][i].Size = new System.Drawing.Size(20, 20);
                    tb[x][i].Location = new System.Drawing.Point(x * 70, i * 25);
                    tb[x][i].Text = i.ToString();
                    this.Controls.Add(tb[x][i]);
                }
            }


Ad
0
 
LVL 10

Author Comment

by:pai_prasad
ID: 16995740
thanks for the answer,,

but how do i add a text_changed event listener and retrieve the value
any links for that?
0
 
LVL 13

Expert Comment

by:devsolns
ID: 16996218
are you kidding me, he took my answer and pasted it in code.  wonderful.
0

Featured Post

Free Tool: ZipGrep

ZipGrep is a utility that can list and search zip (.war, .ear, .jar, etc) archives for text patterns, without the need to extract the archive's contents.

One of a set of tools we're offering as a way to say thank you for being a part of the community.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Introduction Although it is an old technology, serial ports are still being used by many hardware manufacturers. If you develop applications in C#, Microsoft .NET framework has SerialPort class to communicate with the serial ports.  I needed to…
We all know that functional code is the leg that any good program stands on when it comes right down to it, however, if your program lacks a good user interface your product may not have the appeal needed to keep your customers happy. This issue can…
This video shows how to use Hyena, from SystemTools Software, to bulk import 100 user accounts from an external text file. View in 1080p for best video quality.
In an interesting question (https://www.experts-exchange.com/questions/29008360/) here at Experts Exchange, a member asked how to split a single image into multiple images. The primary usage for this is to place many photographs on a flatbed scanner…

856 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question