(Quick Reference) ## isDirty ### Purpose Checks to see if a domain class instance has been modified. ### Examples
    def b = Book.get(1)
    someMethodThatMightModifyTheInstance(b)

    // when called without arguments returns true if any field was changed
    if (b.isDirty()) {
        // can also check if one field has changed
        if (b.isDirty('title')) {
            ...
        }
    }
### Description Parameters: `fieldName` - The name of a field to check | Quick Reference (hide)