my first program

my first program

• jfyfe

  In support of DMan's question, I'd ask the poster to read the suggestions at the top of the forum.

  
  
  

• Gleesha

  hi,

  it will not work because of GoTo's and your lable so if anything was wrong your program will enter an endless recursion, your can use

  var = Double.parse(textbox1.text)

  it will be better

  hope this helps

  
  
  

• Ravi Kumar p

  thanks!!

  it works now

  and i learned something

  bya!

  
  
  

• lponiew

  When you say it doesn't work, what is happening Are you getting an error What is the error message
  
  

• Martín Misol

  hi,

  actualy it doesn't handle more than 2 values , just 2 value is enough like any other calculater one value entered by the user and the other one is saved in the memory(variable) like for example

  textbox to capture the user entry and to display results

  when user type int the textbox 123 and hit a sign(+ - * /) the memory will save 123 when the user type a new value and hit (=) the operation will done memoryVar + textbox.text = value then the memory will hold the new value memroy var = value so if the user make other operation it will be performed againest total value in the memory and the textbox.text

  hope this helps

  
  
  

• SteveInMA

  hi,

  i don't understand why do you keep all those goto statment, and why do you parse things twice

  you have to check your values once , and calculate it in the next step if its truevalue

  1) you can use double.tryparse(variablethatcontainvalue,variabletoholdvalue) for example your textbox1, var1 if this function was able to parse textbox1 it will assign the result to var1, and this function return true if successfull or false if it failed

  2) to make your result textbox appear as double you have to use string.format method

  so your code will look something like this

  Public Class Form1 Private Sub btequal_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btequal.Click Dim checkResult As Boolean Dim var1 As Double Dim var2 As Double checkResult = Double.TryParse(Me.TBvar1.Text, var1) If Not checkResult Then MessageBox.Show("var1 doesn't contain number") Me.TBvar1.Focus() Return End If checkResult = Double.TryParse(Me.TBvar2.Text, var2) If Not checkResult Then MessageBox.Show("var2 doesn't contain number") Me.TBvar2.Focus() Return End If Me.TBresult.Text = String.Format("{0:f2}", operate(var1, Me.tboperation.Text, var2)) End Sub Private Function operate(ByVal var1 As Double, ByVal sign As String, ByVal var2 As Double) As Double Select Case sign Case "+" Return var1 + var2 Case "-" Return var1 - var2 Case "*" Return var1 * var2 Case "/" Return var1 / var2 End Select End Function End Class

  hope this helps

  
  
  

• Paddy Mac

  2cond question:

  how u make it so that it handles more than 2 values behind the comma

  thanks in advance!

  
  
  

• DogGuts

  hy

  i changed my code but stil it dont sees dont commas

  my code:

   

  Public Class Form1

  Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click

  'make vars val1 and val2

  Dim val1 As Double

  Dim val2 As Double

  Dim opr As String

  'set vars val1 and val2 and opr equal to textbox 1,3 and 2 text

  Try

  val1 = Double.Parse(TextBox1.Text)

  Catch ex As Exception

  MessageBox.Show("First number is not a number.")

  GoTo empty

  End Try

  Try

  val2 = Double.Parse(TextBox2.Text)

  Catch ex As Exception

  MessageBox.Show("Second number is not a number.")

  GoTo empty

  End Try

  Try

  opr = tbopr.Text

  Catch ex As Exception

  MessageBox.Show("Operation must be a string")

  GoTo empty

  End Try

  'show message box with val1+val2

  Try

  Dim answer As Double

  If opr = "+" Then

  answer = Double.Parse(val1) + Double.Parse(val2)

  Else

  If opr = "-" Then

  answer = Double.Parse(val1) - Double.Parse(val2)

  Else

  If opr = "*" Then

  answer = Double.Parse(val1) * Double.Parse(val2)

  Else

  If opr = "/" Then

  answer = Double.Parse(val1) / Double.Parse(val2)

  Else

  MessageBox.Show("false operation")

  GoTo empty

  End If

  End If

  End If

  End If

  TextBox3.Text = answer

  Catch ex As Exception

  MessageBox.Show("false operation")

  GoTo empty

  End Try

  Exit Sub

  empty:

  'empty textbox 1 and 2

  TextBox1.Text = ""

  TextBox2.Text = ""

  tbopr.Text = ""

  Exit Sub

  End Sub

  Private Sub ToolStripMenuItem1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ToolStripMenuItem1.Click

  Dim gtform As New SplashScreen1

  gtform.Show()

  End Sub

  Private Sub ToolStripMenuItem2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs)

  Me.Hide()

  End Sub

  Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click

  'make vars val1 and val2

  Dim val1 As Double

  Dim val2 As Double

  Dim opr As String

  'set vars val1 and val2 and opr equal to textbox 1,3 and 2 text

  Try

  val1 = Double.Parse(TextBox1.Text)

  Catch ex As Exception

  MessageBox.Show("First number is not a number.")

  GoTo empty

  End Try

  Try

  val2 = Double.Parse(TextBox2.Text)

  Catch ex As Exception

  MessageBox.Show("Second number is not a number.")

  GoTo empty

  End Try

  Try

  opr = tbopr.Text

  Catch ex As Exception

  MessageBox.Show("Operation must be a +, -, / or *")

  GoTo empty

  End Try

  'show message box with val1+val2

  Try

  Dim answer As Double

  If opr = "+" Then

  answer = Double.Parse(val1) + Double.Parse(val2)

  Else

  If opr = "-" Then

  answer = Double.Parse(val1) - Double.Parse(val2)

  Else

  If opr = "*" Then

  answer = Double.Parse(val1) * Double.Parse(val2)

  Else

  If opr = "/" Then

  answer = Double.Parse(val1) / Double.Parse(val2)

  Else

  MessageBox.Show("false operation")

  GoTo empty

  End If

  End If

  End If

  End If

  Dim anscalc As Double

  anscalc = TextBox3.Text + answer

  TextBox3.Text = anscalc

  Catch ex As Exception

  MessageBox.Show("false operation")

  GoTo empty

  End Try

  Exit Sub

  empty:

  'empty textbox 1 and 2

  TextBox1.Text = ""

  TextBox2.Text = ""

  tbopr.Text = ""

  Exit Sub

  End Sub

  Private Sub Button3_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button3.Click

  TextBox1.Text = "0"

  tbopr.Text = ""

  TextBox2.Text = "0"

  TextBox3.Text = "0"

  End Sub

  End Class

   

   

  i dont understand it anymore

   

  if i do 0.002 + 0.002 it says 4

  if i do 1.02 + 1.301 it says 2321

   

  thanks for repleis!!

  bya

  
  
  
• my first program