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• !! UDFs Explained !!
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• !!A Quick Course on UDFs
• !!Calling UDF from Main Script
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• !!Passing Variables in UDFs
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Variables inside and outside a UDF

Keywords:   Variables inside and outside a UDF global variables local variables

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Question:

I am having trouble with the use of variables. I can use any variable outside the UDF in subroutines that exist outside the UDF and any variable within the UDF works OK within, but I cant seem ot pass the values between. In specific I am loading a droplist box with the selection list and a set of Arrays outside the UDF and the variables maintain the values but I cant use the values in a call to the UDF after a form action has occurred.

Answer:

Variables within the UDF are available only with in the UDF, unless passed to the UDF as a parameter.

You can pass arrays to user-defined functions, and you can return arrays with the Return command.When you pass an array name (ie, not an array element) as a parameter to a function, the array gets passed "by reference". That is, the function receives a pointer to the array, and is therefore able to make changes to it "in place".

In contrast, passing an array element (ie, with a subscript) to a function is like passing a regular string or integer parameter to a function -- it gets passed "by value". Ie, the function receives the value of the array element, but is not able to modify the array itself.

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Article ID:   W15329

File Created: 2002:09:05:13:51:20

Last Updated: 2002:09:05:13:51:20