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BOOK: Beginning C# 3.0 : An Introduction to Object Oriented Programming ISBN: 978-0-470-26129-3
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Old November 4th, 2009, 06:21 PM
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Default Error: Expected class, delegate, or interface struct


I am new to programming and attemting to work my way through your course. I am working on chapter 3; Interger Division app,

I figured out why I was getting errors on the "private void" statements. I needed to add the calc code inside the last bracket.

Now the program compiles without errors, and looks great. It just does not work. I can enter values into poerand 1 and operand2 and I can click the calculate button. and nothing happens. Not even the exit button works. The code is "exact" as in the book.

Below is my code:

using System;
using System.Windows.Forms;
publicclassfrmMain : Form
privateLabel label2;
privateTextBox txtOperand1;
privateTextBox txtOperand2;
privateTextBox txtResult;
privateButton btnCalc;
privateButton btnExit;
privateButton btnClear;
privateLabel label1;
#region Windows Code
privatevoid InitializeComponent()
this.label1 = new System.Windows.Forms.Label();
this.label2 = new System.Windows.Forms.Label();
this.txtOperand1 = new System.Windows.Forms.TextBox();
this.txtOperand2 = new System.Windows.Forms.TextBox();
this.txtResult = new System.Windows.Forms.TextBox();
this.btnCalc = new System.Windows.Forms.Button();
this.btnExit = new System.Windows.Forms.Button();
this.btnClear = new System.Windows.Forms.Button();
// label1
this.label1.AutoSize = true;
this.label1.BorderStyle = System.Windows.Forms.BorderStyle.Fixed3D;
this.label1.Location = new System.Drawing.Point(32, 30);
this.label1.Name = "label1";
this.label1.Size = new System.Drawing.Size(126, 15);
this.label1.TabIndex = 0;
this.label1.Text = " Enter first interger value:";
// label2
this.label2.AutoSize = true;
this.label2.BorderStyle = System.Windows.Forms.BorderStyle.Fixed3D;
this.label2.Location = new System.Drawing.Point(17, 56);
this.label2.Name = "label2";
this.label2.Size = new System.Drawing.Size(142, 15);
this.label2.TabIndex = 1;
this.label2.Text = "Enter second interger value:";
// txtOperand1
this.txtOperand1.Location = new System.Drawing.Point(183, 27);
this.txtOperand1.Name = "txtOperand1";
this.txtOperand1.Size = new System.Drawing.Size(100, 20);
this.txtOperand1.TabIndex = 2;
// txtOperand2
this.txtOperand2.Location = new System.Drawing.Point(183, 54);
this.txtOperand2.Name = "txtOperand2";
this.txtOperand2.Size = new System.Drawing.Size(100, 20);
this.txtOperand2.TabIndex = 3;
// txtResult
this.txtResult.Location = new System.Drawing.Point(28, 93);
this.txtResult.Name = "txtResult";
this.txtResult.Size = new System.Drawing.Size(244, 20);
this.txtResult.TabIndex = 4;
// btnCalc
this.btnCalc.Location = new System.Drawing.Point(28, 143);
this.btnCalc.Name = "btnCalc";
this.btnCalc.Size = new System.Drawing.Size(75, 23);
this.btnCalc.TabIndex = 5;
this.btnCalc.Text = "Calculate";
this.btnCalc.UseVisualStyleBackColor = true;
// btnExit
this.btnExit.Location = new System.Drawing.Point(196, 142);
this.btnExit.Name = "btnExit";
this.btnExit.Size = new System.Drawing.Size(75, 23);
this.btnExit.TabIndex = 6;
this.btnExit.Text = "Exit";
this.btnExit.UseVisualStyleBackColor = true;
// btnClear
this.btnClear.Location = new System.Drawing.Point(111, 202);
this.btnClear.Name = "btnClear";
this.btnClear.Size = new System.Drawing.Size(75, 23);
this.btnClear.TabIndex = 7;
this.btnClear.Text = "Clear";
this.btnClear.UseVisualStyleBackColor = true;
this.btnClear.Visible = false;
// frmMain
this.ClientSize = new System.Drawing.Size(292, 252);
this.Name = "frmMain";
public frmMain()
publicstaticvoid Main()
frmMain main = newfrmMain();
privatevoid btnCalc_Click(object sender, EventArgs e)
bool flag;
float operand1;
float operand2;
float answer;
// Input Step
// Check first input...
flag = float.TryParse(txtOperand1.Text, out operand1);
if (flag == false)
MessageBox.Show("Enter a whole number", "Input Error");
// Check second input
flag = float.TryParse(txtOperand2.Text, out operand2);
if (flag == false)
MessageBox.Show("Enter a whole number", "Input Error");
// Process Step
answer = operand1 / operand2;
// Display Step
txtResult.Text = operand1.ToString() + " divided by " +
operand2.ToString() +
" equals " + answer.ToString();
txtResult.Visible =
privatevoid btnExit_Click(object sender, EventArgs e)

Last edited by cashpot; November 5th, 2009 at 12:18 PM.. Reason: I added Help comments for clarity of question
Old November 5th, 2009, 04:21 PM
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Default Where did this code come from?

Hello Dr. Purdum,

My original problem was with the Interger Division prm in chap. 3. I got errors on compile. I figured out that I needed to add the books code before the last curly bracket at the end of the .cs file. Next, I had an issue of program compiling and not working, just looking pretty.

After grinding it out line by line and two program versions later I finally firgured out why I had no action on my program.

It seems that the Template file from chap. 2 creates a #region Windows Code section and it gets populated during the course of building the form ( I am guessing) Anyway, for some reason my application fails to add two lines of code in both the btnCalc section and the btnExit section. They are as follows:

this.btnCalc.Click += new System.EventHandler(this.btnCalc_Click); &
this.btnExit.Click += new System.EventHandler(this.btnExit_Click);

I found this discrepency by going through your code line by line and compairing it to my code.

I am using Visual C# 2008 Express Edition with SP1.

If I am to complete your textbook course, I will need to know why my program fails to insert thee correct code into the templated area of the .cs file.

Thank you in advance for your help.

Best regards,
Old November 8th, 2009, 08:44 PM
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I'm away from my home on vacation, so I can't check for sure, but did you include the System references as suggested on page 37?
Jack Purdum, Ph.D.
Author: Beginning C# 3.0: Introduction to Object Oriented Programming (and 14 other programming texts)

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