A callback allows the server to (can you guess?) call back into your Web page's code.

回调允许服务器(猜得到吗？)反向调用web页面中的代码。

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Synchronous calls can be programmed, but with timeouts so that if the call can't come back in a certain time, the calling Web service can be unlocked to exit from the system.

同步调用可以通过编程来实现，但带有超时设置，如果调用在一定的时间内未返回，调用Web Services可能取消锁定，从而从系统退出。

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Action that USES a simple XSLT to call the sample back end service via the Web service Proxy, and creates the response message to be sent back to the requesting client.

操作使用一个简单的XSLT通过Web Service Proxy调用样例后台服务，并创建发送回到请求客户端的响应消息。

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