How to use C# to send short messages to mobile phones?

The use of SMS gateway, there are third parties, but also signed with mobile telecommunications. The latter is generally open to big customers. The former, searching for "SMS" in Baidu, can find many companies that provide this service. The provided interface is usually a call to the http protocol. You can use the WebClient class to call it in C# WINFORM. The specific interface still depends on the documents provided by different companies.

Use a short message cat This is a hardware device. You can insert a SIM card and call it through the API provided by SMS Cat … It depends on the API … I used one to provide a dll for you to import. The others should be the same.