成员变量 类型: String # static readonly delete FetchMethod.delete，delete请求 Default Value: 'DELETE' 类型: String # static readonly get FetchMethod.get，get类型请求 Default Value: 'GET' 类型: String # static readonly post FetchMethod.post，post类型请求 Default Value: 'POST' 类型: String # static readonly put FetchMethod.put，put类型请求 Default Value: 'PUT'
