关于 Inserting Hyperlinks Dynamically的功能，没有很明白 returns the name of a bookmark in the same document。
- Values of both uri_or_bookmark_expression and display_text_expression can be of any types. During runtime, Object.ToString() is invoked to get textual representations of these expressions’ values, which is useful for expressions of types like Uri, for example. While building a report, uri_or_bookmark_expression and display_text_expression are evaluated and their results are used to construct a hyperlink that replaces the corresponding link tag then. If uri_or_bookmark_expression returns the name of a bookmark in the same document, then the hyperlink navigates to the bookmark. Otherwise, the hyperlink navigates to a corresponding external resource.
- A link tag cannot be used within a chart.