Tech Tip: How to check if an object property contains a blob
PRODUCT: 4D | VERSION: 20 | PLATFORM: Mac & Win
Published On: September 5, 2023
A blob can be stored in an object property, but since a property value cannot be blob type, using the command Value type on the blob property will return “Is object”. To verify that the property contains a blob, use the command OB Instance of and test it against the 4D.Blob class.
Example:
| var $blob : Blob $obj:={myBlob: $blob} $isObject:=Value type($obj.myBlob) // 38 (Is Object) $isBlob:=OB Instance of($obj.myBlob; 4D.Blob) // True (Is Blob) |