The SqlDataAdapter opens a connection only when required and closes it as soon as it has performed its task.

因为只有当需要的时候应用程序才连接，这样应用程序才更加的可扩展。

youdao

The SqlDataAdapter opens a connection only when required and closes it as soon as it has performed its task.

因为只有当需要的时候应用程序才连接，这样应用程序才更加的可扩展。

youdao