Conversion from string "25." to type 'Double' is not valid.'

Question

Hi All
I Have 2 TextBoxes
I Want To multiplication Decimal Digit.
See My Code ...
Private Sub TextBox1_TextChanged(sender As Object, e As EventArgs) Handles TextBox1.TextChanged
LblResult.Text = Decimal.Parse(TextBox1.Text * TextBox2.Text)
End Sub

But I See this Error..

How To Solve It.
Please Help me
Thanks all

Answer 1

your codes is not work properly
Please Trying Type 25.5 in TextBox1
And See Error

It works for us, so you need to show us what error you are getting.

Note also that the code you posted will throw an exception if either
textbox is empty. So if you start to enter data in TextBox1 while
TextBox2 is empty you will get an exception.

Also, did you try the suggestion from Castorix31 to handle cases
where the default decimal character is not a period? For example:

LlblResult.Text = Decimal.Parse(TextBox1.Text,  
              System.Globalization.CultureInfo.InvariantCulture) *  
            Decimal.Parse(TextBox2.Text,  
              System.Globalization.CultureInfo.InvariantCulture)  
                     
  

Note also that TryParse allows you to test for failure without
getting an exception as happens with Parse.

• Wayne

Answer 2

try this

lblResult.Text = Decimal.Parse(Textbox1.Text) * Decimal.Parse(Textbox2.Text)  

Hope this helps

Answer 3

This is often a language problem for the decimal separator

You can use Decimal.TryParse with a culture for the 3rd parameter
(it works for me with System.Globalization.CultureInfo.InvariantCulture on my french OS)

Answer 4

In addition to the good suggestions you have already received,
note that there is another issue of which you need to be aware

• that of implicit conversions.

The result of your multiplication will be a Decimal. You then
assign that result to what appears to be a string:

lblResult.Text

I'm assuming that lblResult is a Label.

This requires a conversion from a Decimal to a string. That
will happen implicitly if Option Strict is off. However if
Option Strict is on, then you will get an error as this
implicit conversion from a Decimal to a string will not be
allowed. So you need to do the conversion explicitly, by
calling the ToString method of the Decimal. For example:

lblResult.Text = (Decimal.Parse(Textbox1.Text) *   
   Decimal.Parse(Textbox2.Text)).ToString  
  
  

• Wayne

Answer 5

thanks all
your codes is not work properly
Please Trying Type 25.5 in TextBox1
And See Error