Ever wanted to check if a property in a 4D object is a picture? Here is a utility to determine if it is:

// ---------------------------------------------------------------------- // Name: DETERMINE_OBJ_PROP_IS_PICTURE // Description: Method will determine if a specific property in a 4D obejct // is a picture. // // Parameters: // $1 (PICTURE) - Input of a Object property that might be a picture. // // Output: // $0 (BOOLEAN) - True - Property is a picture, False - It is not. // ---------------------------------------------------------------------- C_PICTURE($1) C_BOOLEAN($0) If ($1=Null)   $0:=False Else   $0:=True End if

Example #1 Checking a picture property in object notation:

C_OBJECT($o;$Avatar) C_PICTURE($img) C_BOOLEAN($result) READ PICTURE FILE("4D.png";$img;*) OB SET NULL($o;"$Avatar") $o.$Avatar:=$img // setting the picture with object notation $result:=DETERMINE_OBJ_PROP_IS_PICTURE ($o.$Avatar) // True

Example #2: Checking a picture property with OB SET:

OB SET($o;"$Avatar";$img) $result:=DETERMINE_OBJ_PROP_IS_PICTURE (OB Get($o;"$Avatar")) // True

Example #3: Checking a picture property that is not a picture in object notation:

$o.$Avatar:="Not Picture" $result:=DETERMINE_OBJ_PROP_IS_PICTURE ($o.$Avatar) // False

Example #4: Checking a picture property that is not a picture with OB SET:

OB SET($o;"$Avatar";"Not Picture") $result:=DETERMINE_OBJ_PROP_IS_PICTURE (OB Get($o;"$Avatar")) // False