asp.net+mysql解决Incorrect string value: '\xF0\x9F\x98\xAD

1. ALTER DATABASE 数据库 CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci;
2. ALTER TABLE 表 CONVERT TO CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci;
3. 数据库连接字符串加上：charset=utf8mb4