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Renders an HTML element as an anchor definition (if "linkName" is specified) or as a hyperlink to the specified URL. URL rewriting will be applied automatically, to maintain session state in the absence of cookies. The content displayed for this hyperlink will be taken from the body of this tag.
The base URL for this hyperlink is calculated based on which of the following attributes you specify (you must specify exactly one of them):
- forward - Use the value of this attribute as the name of a global ActionForward to be looked up, and use the application-relative or context-relative URI found there.
- action - Use the value of this attribute as the name of a Action to be looked up, and use the application-relative or context-relative URI found there.
- href - Use the value of this attribute unchanged.
- page - Use the value of this attribute as a application-relative URI, and generate a server-relative URI by including the context path and application prefix.
Normally, the hyperlink you specify with one of the attributes described in the previous paragraph will be left unchanged (other than URL rewriting if necessary). However, there are two ways you can append one or more dynamically defined query parameters to the hyperlink -- specify a single parameter with the paramId attribute (and its associated attributes to select the value), or specify the name (and optional property) attributes to select a java.util.Map bean that contains one or more parameter ids and corresponding values.
To specify a single parameter, use the paramId attribute to define the name of the request parameter to be submitted. To specify the corresponding value, use one of the following approaches:
- Specify only the paramName attribute - The named JSP bean (optionally scoped by the value of the paramScope attribute) must identify a value that can be converted to a String.
- Specify both the paramName and paramProperty attributes - The specified property getter method will be called on the JSP bean identified by the paramName (and optional paramScope) attributes, in order to select a value that can be converted to a String.
If you prefer to specify a java.util.Map that contains all of the request parameters to be added to the hyperlink, use one of the following techniques:
- Specify only the name attribute - The named JSP bean (optionally scoped by the value of the scope attribute) must identify a java.util.Map containing the parameters.
- Specify both name and property attributes - The specified property getter method will be called on the bean identified by the name (and optional scope) attributes, in order to return the java.util.Map containing the parameters.
As the Map is processed, the keys are assumed to be the names of query parameters to be appended to the hyperlink. The value associated with each key must be either a String or a String array representing the parameter value(s), or an object whose toString() method will be called. If a String array is specified, more than one value for the same query parameter name will be created.
Additionally, you can request that the current transaction control token, if any, be included in the generated hyperlink by setting the transaction attribute to true. You can also request that an anchor ("#xxx") be added to the end of the URL that is created by any of the above mechanisms, by using the anchor attribute.
本文来自ChinaUnix博客,如果查看原文请点:http://blog.chinaunix.net/u/29515/showart_226819.html |
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