服务端更新消息能体现，但是再发一条消息或者退出聊天界面再次进入又变成原本的内容。求帮助 自定消息代码如下： 收到服务端消息的时候 decode中binaryContent数据是想要的。

export default class BuyVehicleRequestMessageContent extends MessageContent {
    content;
    orderInfo;

    constructor(content, extra, mentionedType = 0, mentionedTargets = []) {
        super(MessageContentType.MESSAGE_CONTENT_TYPE_BUYVEHICLE_REQUEST, mentionedType, mentionedTargets);
        this.content = content;
        this.orderInfo = extra
    }

    digest() {
        return "[定车申请]";
    }

    encode() {
        let payload = super.encode();
        payload.searchableContent = this.content;
        payload.binaryContent = wfc.utf8_to_b64(JSON.stringify(this.orderInfo));
        return payload;
    }

    decode(payload) {
        super.decode(payload);
        console.log("开始:decode")
        this.content = payload.content;
        this.searchableContent = payload.searchableContent
        if (payload.binaryContent && payload.binaryContent.length > 0) {
            // JSON.parse 和 JSON.stringify 不能处理java long
            payload.extra =JSON.parse(wfc.b64_to_utf8(payload.binaryContent))
            console.log("orderState:"+payload.extra.orderState)
            this.binaryContent = payload.binaryContent
            this.extra = payload.extra
        }
    }
}