CDbl? What is it?

[Uifz]

Hi, I'm trying to create an inputbox for uiJob1TextBox, uiJob2TextBox, and uiJob3TextBox. This way the user will be asked to enter a number for each textbox. Now I have my code:

Const RaisePercentage As String = "Raise Percentage: "
        Dim job1HP As Double, job2HP As Double, job3HP As Double
        Dim job1NewHP As Double, job2NewHP As Double, job3NewHP As Double
        Dim raisePercent As Double
        Try
            job1HP = CDbl(uiJob1TextBox.Text)
            job2HP = CDbl(uiJob2TextBox.Text)
            job3HP = CDbl(uiJob3TextBox.Text)
        Catch ex As Exception
            MsgBox(ex.Message(), MsgBoxStyle.Critical)
            uiJob1TextBox.Focus()
            Exit Sub
        End Try
        Do
            Try
                raisePercent = CDbl(InputBox("Please enter the raise percentage.", "Raise Percentage")) / 100
                Exit Do
            Catch ex As Exception
                MsgBox(ex.Message(), MsgBoxStyle.Critical)
            End Try

I'm trying to understand what CDbl is? Because I'm thinking if i use the 'Try' statement and make job1HP equal to something else that contains in (uiJob1Textbox)
That then I can create a raisePercent= "blah" code which will allow me to enter a InputBox for the three textboxes. Anyone have any suggestions or what
CDbl means and if I can use a different expression so this way I can have expression A equal uiJobTextbox, expression B equal textbox2, and expression C equal textbox3.

Thanks!

[jcis]

CDbl() = Convert.ToDouble()
In this case it's ok as your variables are declared as Double

[Uifz]

Oh Ok, So any idea how I Could create an inputbox message allowing the user to enter data into each of the three textboxes separately?

[Uifz]

I think I'm close, I'm trying to enter

Try
            job1HP = CDbl(uiJob1TextBox.Text)
 
        Catch ex As Exception
            MsgBox(ex.Message(), MsgBoxStyle.Critical)
            uiJob1TextBox.Focus()
            Exit Sub
        End Try
        Do
            Try
                raisePercent = CDbl(InputBox("Please enter the raise percentage for Job 1.", "Raise Percentage")) / 100
                Exit Do
            Catch ex As Exception
                MsgBox(ex.Message(), MsgBoxStyle.Critical)
            End Try

As separate "Try-Catch" statements. Will this work? It looks like it could.

[jmcilhinney]

You shouldn't be using CDbl like that. It is bad practice to just force a conversion and then clean up the mess if it fails. You should only use CDbl if you know for a fact that the value is, or can be converted to, a Double. You should be using Double.TryParse as it does not throw an exception if the converson fails, e.g.

Dim myDouble As Double
 
        If Double.TryParse(myString, Globalization.NumberStyles.Float, Nothing, myDouble) Then
            'The conversion was successful and the value was stored in myDouble.
        Else
            'The conversiuon failed.
        End If

If you're using 2005 (which you haven't specified, please use the radio buttons provided when starting threads in future) you can omit the second and third parameters.