按如下所示更改逻辑

  var selectedMembers = [String: String]()
    var smembers = [String]()
    var selected = ""

if selectedMembers.isEmpty == false {
            for (key, value) in selectedMembers {
                selected = String(format: "{\"\\email\\\":\"\\%@\"\\,\"\\category\"\\:\"\\%@\"\\}", arguments: [key,value])
                smembers.append(selected)
            }
        }

然后输入您的帖子数据

let parameters: Parameters = [
            "topic":topicTextField.text!,
            "setdate":currentDate as String,
            "scheduledate":setDate as String,
            "settime":currentTime as String,
            "scheduletime":setTime as String,
            "agenda":agendaTextField.text!,
            "adminname":"abcname",
            "type":"meeting",
            "users" :"[\(smembers.joined(separator: ","))]",
            "adminemail":"abc@gmail.com"
        ]