VS 2015 Checking person age-VBForums
Results 1 to 10 of 10

Thread: Checking person age

  1. #1

    Thread Starter
    New Member
    Join Date
    Dec 2017
    Posts
    13

    Checking person age

    Hello, I'm working on the form where I want the user to enter their date of birth and if is under 18 they will see the message box. The form consist of 2 textboxes: Day, Year and one combobox with list of Months. At the moment no matter what year I enter everything is passing through.

    Code:
    Code:
    Private Sub btnContinue_Click(sender As Object, e As EventArgs) Handles btnContinue.Click
    
            Dim currentYear As Integer = Today.Year
            Dim CURRENTmONTH As Integer = Today.Month
            Dim CurrentDay As Integer = Today.Day
    
            Dim birthYear As Integer = Integer.TryParse(txtYear.Text, birthYear)
            Dim birthMonth As Integer = Integer.TryParse(cboMonths.SelectedIndex - 1, birthMonth)
            Dim birthDay As Integer = Integer.TryParse(txtDay.Text, birthDay)
    
            Dim Age As Integer = currentYear - birthYear
    
            If CURRENTmONTH = birthMonth Then
    
                If CurrentDay < birthDay Then
                    Age -= 1
                End If
            ElseIf CURRENTmONTH < birthMonth Then
                Age -= 1
            ElseIf Age < 18 Then
                MessageBox.Show("You're not old enough to register. Use guest Account")
            Else
                MessageBox.Show("You're good to go")
            End If
    
    
        End Sub
    Last edited by Shaggy Hiker; Dec 29th, 2017 at 10:31 AM. Reason: Added CODE tags.

  2. #2
    Super Moderator Shaggy Hiker's Avatar
    Join Date
    Aug 2002
    Location
    Idaho
    Posts
    31,292

    Re: Checking person age

    Welcome to the forums. I edited your post to add [CODE][/CODE] tags which you can do by pressing the # button and pasting the code between the resulting tags.


    As for the question, you'd be better off using a DateTimePicker to get the birthday than using a trio of textboxes, but that's up to you. In any case, TryParse doesn't return an integer, it returns a Boolean, so for the code to even compile, you must have Option Strict OFF. If you turn Option Strict ON, you'll probably find several problems, and they are all worth fixing.

    If you stick with the integers, you might as well just turn them into a date:
    Code:
    dim birthDate = new Date(birthYear,birthMonth,birthDay)
    at which point you can do something like this:
    Code:
    If (date.Today-birthDate).TotalYears<18 Then
    However, if you want to go the way you are, then fix the problem with TryParse, then put a breakpoint on the first If statement and step through the code to see what is happening. This is an excellent place to learn breakpoints and code stepping. If the code isn't doing what you expect, don't guess at why not. With a breakpoint, you can pause the code at any line and see what all the variables hold, then step forwards line by line (F11) and watch the variables change, see which branches are taken at any If statement, and so on.
    My usual boring signature: Nothing

  3. #3
    Fanatic Member ChrisE's Avatar
    Join Date
    Jun 2017
    Location
    Frankfurt
    Posts
    826

    Re: Checking person age

    Hi,

    use Dtp like Shaggy said, or I would just use a Textbox
    Code:
     Private Sub Button4_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button4.Click
            Dim Birth As Date = TextBox4.Text
            If Date.TryParse(Birth, TextBox4.Text) = False Then
                MessageBox.Show("wrong Date !")
            End If
            Dim year, month, day As Integer
            While year <= (Now.Year - Birth.Year)
                While month <= (Now.Month - Birth.Month)
                    While day <= (Now.Day - Birth.Day)
                        day += 1
                    End While
                    month += 1
                End While
                year += 1
            End While
            year -= 1 : month -= 1 : day -= 1
            If year < 18 Then
                MessageBox.Show("You're not old enough to register. Use guest Account")
            End If
            Label1.Text = (year & " year(s) " & month & " month(s) " & day & " day(s)")
        End Sub
    regards
    Chris
    to hunt a species to extinction is not logical !
    since 2010 the number of Tigers are rising again in 2016 - 3900 were counted. with Baby Callas it's 3901, my wife and I had 2-3 months the privilege of raising a Baby Tiger.

  4. #4

    Thread Starter
    New Member
    Join Date
    Dec 2017
    Posts
    13

    Re: Checking person age

    Hi Shaggy and ChrisE, thanks for helping me out. I have tried use breakpoint, and I notice that since that line the value is set to -1 for some reason and is using -1 for all calculations. I wonder why is increasing year to 2018 instead of 2016, since is suppose to calculate 2017-1? Is it because of 2017-(-1)=2018? Thanks. PS: Iam not quick at learning. Thank you for patience.
    Code:
    Code:
    Dim birthYear As Integer = Integer.TryParse(txtYear.Text, birthYear)
            Dim birthMonth As Integer = Integer.TryParse(cboMonths.SelectedIndex - 1, birthMonth)
            Dim birthDay As Integer = Integer.TryParse(txtDay.Text, birthDay)

  5. #5
    PowerPoster techgnome's Avatar
    Join Date
    May 2002
    Posts
    31,337

    Re: Checking person age

    You're using TryParse wrong... TryParse returns a BOOLEAN VALUE ... indicating if the conversion was successful or not. The numerical conversion is returned through the second parameter. So it returns the value through the output parameter, but then you immediately overwrite it by stuffing the true/false return value into the integer value. The code should look likle this:
    Code:
    Dim birthYear As Integer = 0
    Dim birthMonth As Integer = 0
    Dim birthDay As Integer = 0
    
    If Integer.TryParse(txtYear.Text, birthYear) andalso Integer.TryParse(cboMonths.SelectedIndex - 1, birthMonth) andalso Integer.TryParse(txtDay.Text, birthDay) Then 
    ... work with the values here
    else
    .. one or more of the conversions was bad
    end if
    -tg
    * I don't respond to private (PM) requests for help. It's not conducive to the general learning of others.*
    * I also don't respond to friend requests. Save a few bits and don't bother. I'll just end up rejecting anyways.*
    * How to get EFFECTIVE help: The Hitchhiker's Guide to Getting Help at VBF - Removing eels from your hovercraft *
    * How to Use Parameters * Create Disconnected ADO Recordset Clones * Set your VB6 ActiveX Compatibility * Get rid of those pesky VB Line Numbers * I swear I saved my data, where'd it run off to??? *

  6. #6

    Thread Starter
    New Member
    Join Date
    Dec 2017
    Posts
    13

    Re: Checking person age

    Is working now, thank you, guys. I really appreciate you took your time to help me. Thanks again

  7. #7
    Super Moderator Shaggy Hiker's Avatar
    Join Date
    Aug 2002
    Location
    Idaho
    Posts
    31,292

    Re: Checking person age

    As I said earlier, if you turn Option Strict ON, it would have shown this problem. Option Strict is off by default, but that allows you to do unsafe conversions, so it's best to set Option Strict ON in either the project or for ALL projects using Options (Under Projects and Solutions on the VB Defaults tab).
    My usual boring signature: Nothing

  8. #8

    Thread Starter
    New Member
    Join Date
    Dec 2017
    Posts
    13

    Re: Checking person age

    Thanks for the tip I'll enable from now on.Is there any way to compare two strings from two textboxes.
    Textbox1.Text = TextBox2.Text doesn't work.

  9. #9
    Super Moderator Shaggy Hiker's Avatar
    Join Date
    Aug 2002
    Location
    Idaho
    Posts
    31,292

    Re: Checking person age

    In what way does it not work, cause that should work...fairly well. There are ways it can fail if you do it that way. For one thing, the capitalization has to be the same. If you don't want to care about that you can use String.Equals, which has several overloads. One of the overloads takes a third argument, which you would set to CurrentCultureIgnoreCase (or whatever option like that Intellisense gives you).

    That won't take care of hidden spaces, though. A leading or trailing space would be invisible, and darn hard to see unless you are using a font that has all characters taking up the same width (TrueType fonts, I think). You can use String.Trim() to get rid of any leading or trailing spaces, but that still leaves the case where somebody put two spaces between words. There are two spaces between two of the words in the last sentence, but you may not see which two. Similarly, that can be hard to see in a textbox, and I don't know any good way to catch that.

    For strings to be equal, they really have to be equal, including in their hidden characters. Trim takes care of leading and trailing characters...beyond that you're a bit hosed.
    My usual boring signature: Nothing

  10. #10

    Thread Starter
    New Member
    Join Date
    Dec 2017
    Posts
    13

    Re: Checking person age

    Well I make mistake now I know why wasn't working. I have came up with something like this? Is working well. My programming level is just beginner do you think I could improve som
    Do you think is appropriate to use textchanged event for txtConfPass? Thanks
    Code:
    Code:
    Private Sub txtPassword_KeyPress(sender As Object, e As KeyPressEventArgs) Handles txtPassword.KeyPress
            If Char.IsLetterOrDigit(e.KeyChar) And txtPassword.Text.Length < 7 or e.KeyChar= ControlsChars.Back Then
                e.Handled = False
            Else
                e.Handled = True
                lblErrPass.Visible = True
                lblErrPass.Text = "Password can consit of letters, numbers and up to 7 characters"
    
            End If
    End Sub
    
     Private Sub txtConfPass_TextChanged(sender As Object, e As EventArgs) Handles txtConfPass.TextChanged
            If (txtConfPass.Text <> txtPassword.Text) Then
                lblPassCheck.Visible = True
                lblPassCheck.Text = "Password don't match."
            ElseIf (txtConfPass.Text = txtPassword.Text) Then
                lblPassCheck.Visible = True
                lblPassCheck.Text = "Correct."
            End If
    End Sub
    Last edited by BloodySandwich; Dec 29th, 2017 at 04:43 PM. Reason: code editing

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  



Featured


Click Here to Expand Forum to Full Width

Survey posted by VBForums.