The Init Property (Magic xpa 4.x)

In some cases, the Init property of a variable is evaluated on the server, for example for a column in Create mode, and in other cases is evaluated on the client, such as a local variable.

Since it is not possible to know when the property will be evaluated, the functions used within the expressions need to be neutral functions, meaning neither server-side nor client-side. But often, there is a necessity to use a function belonging to one of the groups. Client-side expressions cannot be used in the Init property. However, if you need to use a client-side expression in an Init property, do the following:

1. Define a new variable that will hold the function's value.

2. Within the Record Prefix, update the variable with the relevant expression.

3. Remember that if you are dealing with a field from a table, the initialization is only valid when the task is in Create mode. Therefore, you need to condition the Update operation with Stat (0,'C'Mode).

In this example, there are three fields with Inits.

• The first one uses a Neutral expression, which has no marking to the left. This one is OK.

• The second Init uses the Menu() function, which creates a client-side expression. This will generate a syntax error message.

• The third Init uses CallProg(), which makes a server-side expression. This will also generate a syntax error message.

If you need to use client-side or server-side expressions in an Init, use an Update Variable operation instead.

• For Server-side expressions, it is recommended to do the update in Task Prefix in order to avoid extra access to the server.

• For Client-side expressions, do the update in Record Prefix.

If your Init is for a newly-created record, you should do the update in Record Prefix, using Stat(0,'C'MODE) in the Condition property.