Does a Control Exist?

Ray ray at linkit.com
Sun Nov 24 11:58:48 EST 2013


Yeah, I know there are various ways of checking whether the control 
exists or not before proceeding.  I just wondered whether anybody else 
thought it might be nice not to have to do that since it does halt the 
script if the control doesn't exist.

On 11/24/2013 11:46 AM, Richmond wrote:
> On 24.11.2013 18:31, Ray wrote:
>> After loosely following the item delimiter thread last week a similar 
>> idea came to me today which might be an interesting discussion.
>>
>> It's often time consuming to type spell out...
>>    if there is a field "My Field" then put field "My Field" into myVar
>>
>> If I don't first check to see if the control exists [and it doesn't] 
>> I get an error and the script stops execution.
>>
>> I don't have to do this with a custom property.  That is if the 
>> script is...
>>    put the NewProperty of this card into myVar
>> and said property doesn't exist, I simply end up with nothing in 
>> myVar, but it doesn't cause an error and the script continues.
>>
>> Does anybody think it would be worth it to have a way to stop errors 
>> from being produced when referring to non-existent controls?
>>
>> Ray Horsley
>> LinkIt! Software
>>
>
> Well, surely the trick is to do something like this:
>
> if exists(fld "My Field") then
>     put fld "My Field" into myVar
> end if
>
> Easy-Peasy-Lemon-Squeezy!
>
> Richmond.
>
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