The Exif standard defines the following data types for comments. Usage is dependent on your development system. To see the usage, refer to the code example for your system.
|
Data type |
Description |
|---|---|
|
The data type is determined by the field. |
|
|
SHORT |
Integer. |
|
LONG |
Long integer. |
|
Character string. |
|
|
BYTE |
Array of bytes. |
|
An array of two unsigned long integers that express a fraction. The first value is the numerator, and the second is the denominator. (Visual Basic does not recognize unsigned long integers and will interpret large values, as negative values.) |
|
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An array of two signed long integers that express a fraction. The first value is the numerator, and the second is the denominator. |
The length of a comment is based on the data type. For example, a RasterTagMetadataDataType.Rational with a length of 3 is an array of 6 long integers.
When you set a comment that requires an array, the array can be zero-based or 1-based (where the first element has an index of 1). When you get a comment that is an array, it will always be zero-based (where the first element has an index of 0).
When you assign comments, the ActiveX does data type conversions for you. For example, if a comment is RasterTagMetadataDataType.URational with a length of 3, you can assign an array of six integers. If you assign an invalid value, the value is ignored.