IsValid
PowerScript function
Description
Determines whether an object variable is instantiated — whether its
value is a valid object handle.
Syntax
|
1 |
IsValid ( objectvariable ) |
|
Argument |
Description |
|---|---|
|
objectvariable |
An object variable or a variable of type Any — typically |
Return value
Boolean.
Returns true if objectvariable is an instantiated object. Returns
false if objectvariable is not an object, or if it is an object that is
not instantiated. If objectvariable is null, IsValid returns null.
Usage
Use IsValid instead of the Handle function to determine whether a
window is open.
Examples
This statement determines whether the window w_emp is open and if it
is not, opens it:
|
1 |
IF IsValid(w_emp) = FALSE THEN Open(w_emp) |
This example returns -1 because the IsValid function returns false.
Although the objectvariable argument is a valid string, it is not an
instantiated object. The IsValid method would return true only if la_value
was an instantiated object:
|
1 2 3 4 |
any la_value la_value = "I'm a string" IF NOT IsValid(la_value) THEN return -1 |
See also