最近几年来，地理信息系统无论是在理论上还是应用上都处在一个飞速发展的阶段。 GIS被应用于多个领域的建模和决策支持，如城市管理、区划、环境整治等等，地理信息成为信息时代重要的组成部分之一； “数字地球”概念的提出，更进一步推动了作为其技术支撑的GIS的发展。 与此同时，一些学者致力于相关的理论研究，如空间感知、空间数据误差、空间关系的形式化等等。 这恰好说明了地理信息系统作为应用技术和学科的两个方面，并且这两个方面构成了相互促进的发展过程。
Optional SOAP The optional SOAP Header element can contain application-specific information about SOAP messages (such as authentication, payments, and so on). If Note: all The above example contains a header with a “Trans” element with a value of 234. the value of the “mustUnderstand” attribute of this element is “1”. SOAP is in the default namespace (” http://www.w3.org/2001/12/soap-envelope ”) defines three attributes.” These three attributes are: The mustUnderstand property of SOAP can be used to identify whether the title item is mandatory or optional for the recipient to process it. If you add “mustUnderstand=” 1 “to a child element of the Header element,it indicates that the recipient processing the header must recognize the element. If the recipient cannot recognize the element, it must fail to process the header. SOAP messages can be propagated from a sender to a receiver by passing through different endpoints along the message path. Not all parts of the SOAP message are intended to be delivered to the final endpoint of the SOAP message, but on the other hand, it may be intended to be delivered to one ormore endpoints on the message path. SOAP’s SOAP’s There is no default encoding for SOAP messages. Header element contains header information. 3.5.1. SOAP Header element ¶
Header element is provided, it must be a Envelope the first child of the element. Header the immediate child element of the element must be a qualified namespace.
actor 、 mustUnderstand and encodingStyle . These properties, defined in the SOAP header, define howthe container handles SOAP messages. 3.5.2. MustUnderstand attribute ¶
Grammar ¶
soap:mustUnderstand="0|1"
Example ¶
3.5.3. Actor attribute ¶
actor property can be used to set the Header element is addressed to a specific endpoint.Grammar ¶
soap:actor="*URI*"
Example ¶
3.5.4. EncodingStyle attribute ¶
encodingStyle property is used to define the data type used in the document. This attribute can appear in any SOAP element and is applied to the contents of the element and to all child elements of the element.Grammar ¶
soap:encodingStyle="*URI*"