added button disables when not needed in ButtonUpdate

ElementaryMathematics/Form1.Designer.cs

@@ -191,6 +191,7 @@
             this.btnReset.TabIndex = 9;
             this.btnReset.Text = "Reset";
             this.btnReset.UseVisualStyleBackColor = true;
+            this.btnReset.Click += new System.EventHandler(this.btnReset_Click);
             // 
             // btnClear
             // 
@@ -200,6 +201,7 @@
             this.btnClear.TabIndex = 8;
             this.btnClear.Text = "Clear";
             this.btnClear.UseVisualStyleBackColor = true;
+            this.btnClear.Click += new System.EventHandler(this.btnClear_Click);
             // 
             // btnShowCorrectAnswer
             // 
@@ -278,7 +280,7 @@
             this.chkShowSummary.TabIndex = 4;
             this.chkShowSummary.Text = "Display Summary Information";
             this.chkShowSummary.UseVisualStyleBackColor = true;
-            this.chkShowSummary.CheckedChanged += new System.EventHandler(this.checkBox1_CheckedChanged);
+            this.chkShowSummary.CheckedChanged += new System.EventHandler(this.chkSummary_CheckedChanged);
             // 
             // btnExit
             // 

ElementaryMathematics/Form1.cs

@@ -22,12 +22,17 @@ namespace ElementaryMathematics
         private Int32 numRunningCorrect = 0;
         private Int32 numRunningIncorrect = 0;
 
+        private bool hasTried = false;
         
         
         public Form1()
         {
             InitializeComponent();
-            //test
+
+            pnlSummary.Visible = false;
+            lblNumCorrect.Text = "0";
+            lblNumIncorrect.Text = "0";
+            UpdateButtons();
         }
 
         private void groupBox1_Enter(object sender, EventArgs e)
@@ -40,9 +45,18 @@ namespace ElementaryMathematics
             // throw new System.NotImplementedException();
         }
 
-        private void checkBox1_CheckedChanged(object sender, EventArgs e)
+        private void chkSummary_CheckedChanged(object sender, EventArgs e)
         {
-            // throw new System.NotImplementedException();
+
+            if (chkShowSummary.Checked)
+            {
+                pnlSummary.Visible = true;
+            }
+            else
+            {
+                pnlSummary.Visible = false;
+            }
+            
         }
 
         private void button1_Click(object sender, EventArgs e)
@@ -122,15 +136,19 @@ namespace ElementaryMathematics
                 if (isAdd)
                 {
                     answer = a + b;
+                    hasTried = true;
                 }else if (isSubtract)
                 {
                     answer = a - b;
+                    hasTried = true;
                 }else if (isMultiply)
                 {
                     answer = a * b;
+                    hasTried = true;
                 }else if (isDivide)
                 {
                     answer = a / b;
+                    hasTried = true;
                 }
                 else
                 {
@@ -152,7 +170,7 @@ namespace ElementaryMathematics
             
             lblMessage.Text = "Good Job!";
             numRunningCorrect++;
-            
+            lblNumCorrect.Text = numRunningCorrect.ToString();
         }
 
         private void Fail()
@@ -160,7 +178,7 @@ namespace ElementaryMathematics
 
             lblMessage.Text = "Try Again";
             numRunningIncorrect++;
-            
+            lblNumIncorrect.Text = numRunningIncorrect.ToString();
         }
         
         
@@ -233,21 +251,98 @@ namespace ElementaryMathematics
                 
             }
             
+            UpdateButtons();
+            
         }
 
         private void txtA_TextChanged(object sender, EventArgs e)
         {
             ep1.Clear();
+            hasTried = false;
+            UpdateButtons();
         }
 
         private void txtB_TextChanged(object sender, EventArgs e)
         {
             ep1.Clear();
+            hasTried = false;
+            UpdateButtons();
         }
 
         private void txtC_TextChanged(object sender, EventArgs e)
         {
             ep1.Clear();
+            hasTried = false;
+            UpdateButtons();
+            lblMessage.Text = "";
+        }
+
+        private void btnClear_Click(object sender, EventArgs e)
+        {
+            txtA.Clear();
+            txtB.Clear();
+            txtC.Clear();
+            
+            UpdateButtons();
+        }
+
+        private void btnReset_Click(object sender, EventArgs e)
+        {
+            btnClear_Click(sender, e);
+
+            numRunningCorrect = 0;
+            numRunningIncorrect = 0;
+            
+            UpdateButtons();
+            rdoAddition.Select();
+
+        }
+
+        private void UpdateButtons()
+        {
+
+            if (txtA.TextLength > 0 && txtB.TextLength > 0 && txtC.TextLength > 0)
+            {
+
+                btnChkAnswer.Enabled = true;
+
+            }
+            else
+            {
+                btnChkAnswer.Enabled = false;
+            }
+
+            if (hasTried)
+            {
+                btnShowCorrectAnswer.Enabled = true;
+            }
+            else
+            {
+                btnShowCorrectAnswer.Enabled = false;
+            }
+            
+            if (txtA.TextLength > 0 || txtB.TextLength > 0 || txtC.TextLength > 0)
+            {
+
+                btnClear.Enabled = true;
+
+            }
+            else
+            {
+                btnClear.Enabled = false;
+            }
+
+            if (numRunningCorrect > 0 || numRunningIncorrect > 0)
+            {
+
+                btnReset.Enabled = true;
+
+            }
+            else
+            {
+                btnReset.Enabled = false;
+            }
+            
         }
     }
 }