Change value into exponential form

[Shahzad Ali]

I have a double type variable Sum and more than 1 textbox. When i divide one textbox value to another textbox value i got result of this type .00000000438000 and assign this value to another textbox. I want to change this value into exponentional form like 4.3*10-9. In which way i will change this value. I m trying my best effort bt i can't do this. Can someone help me?

[kadghar]

VB will change it if the value is less than 1*10^-15.

Never the less, the capital "E" is recognized as a numeric value... Lets write a fast function to do that (it will return a string that can be used as a number with the VAL function for later uses)

Function myExponential(byval Dou1 as double) as String
    Dim Exponent as integer = 0
    Do
        If Dou1 < 0 then
            Dou1 *= 10
            Exponent -= 1
        ElseIf Dou1 >= 10 then
            Dou1 /= 10
            Exponent += 1
        Else
            Return Dou1.ToString & IIF(Exponent <> 0, "E" & Exponent.ToString, Nothing)
    Loop
End Function