When the system sends this message as a result of a SystemParametersInfo call, the wParam parameter is the value of the uiAction parameter passed to the SystemParametersInfo function. For a list of values, see SystemParametersInfo.When the system sends this message as a result of a change in policy settings, this parameter indicates the type of policy that was applied. This value is 1 if computer policy was applied or zero if user policy was applied.When the system sends this message as a result of a change in locale settings, this parameter is zero.When an application sends this message, this parameter must be NULL.
When the system sends this message as a result of a SystemParametersInfo call, the wParam parameter is the value of the uiAction parameter passed to the SystemParametersInfo function. For a list of values, see SystemParametersInfo.When the system sends this message as a result of a change in policy settings, this parameter indicates the type of policy that was applied. This value is 1 if computer policy was applied or zero if user policy was applied.When the system sends this message as a result of a change in locale settings, this parameter is zero.When an application sends this message, this parameter must be NULL.
IPAddress.Parse 方法
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