[IronPython] Newbie: convert string to python expression??

[Michael Foord]

context = {}

def inputBox_KeyDown(s, e):
    root.message.Text = ''
    key = e.Key.value__
    result = root.inputBox.Text
    if key == 3: #If 'Enter' key is pressed
	try:
          try:
            root.message.Text = eval(result)
          except SyntaxError:
            exec result in context
       except Exception, e:
         print 'Unhandled exception', e

Note the "exec result in context" and my suggested changes to your 
exception handling.

Michael


xkrja wrote:
> Thanks for the reply.
>
> Below is a snippet of what I've got:
>
> def inputBox_KeyDown(s, e):
>     root.message.Text = ''
>     key = e.Key.value__
>     result = root.inputBox.Text
>     if key == 3: #If 'Enter' key is pressed
>         try:
>           root.message.Text = eval(result)
>         except:
>           exec result
>          
> root = Application.Current.LoadRootVisual(UserControl(), "app.xaml")
> sys.stdout = Writer(root.message)
>
> root.inputBox.KeyDown += inputBox_KeyDown
>
> Can't I just put everthing that is evaluated or executed in some kind of
> global scope so that they can be accessed just like in the console? If not:
> I looked a little at dictionaries but didn't really understand how to use
> them in this case? Can someone give me a short example that can be used for
> my case?
>
> Once again, thanks for all help!
>
>
> Michael Foord-5 wrote:
>   
>> You've snipped the code so I can't see it exactly, but I'm pretty sure 
>> you are doing this inside a method. This will create a new 'scope' every 
>> time you enter the method and so you are creating a local variable that 
>> disappears when you exit the method.
>>
>> When you exec you can provide a dictionary as a context for the 
>> execution to happen in. If you store this as an instance member and 
>> re-use the same execution context every time then changes will be 
>> 'remembered'.
>>
>> Michael
>>
>>     
>
>   


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