Flutter，如何在添加到串列之前確定配接器是否包含字串

我正在將專案添加到這樣的串列中。我有一個像這樣的名為 BuyHistoryModel 的檔案

class buyHistoryModel{

String symbol, ticketNumber, orderNumber,datePlaced, dateMatched, timeInForce, 
 bidPrice, matchPrice,
    volume, status;

buyHistoryModel(
  {
    required this.symbol,
    required this.ticketNumber,
    required this.orderNumber,
    required this.datePlaced,
    required this.dateMatched,

    required this.timeInForce,
    required this.bidPrice,
    required this.matchPrice,
    required this.volume,
    required this.status

  }
  );

}

然后我有一個資料構建器，我可以在其中提供資料

//data of buy history
import 'package:zse_direct_flutter/models/buyhistory_model.dart';



class BuyHistoryAdapter {
  List getBuyHistory() {
    return [
      buyHistoryModel(
        symbol: "FCA.ZW",
        ticketNumber: "216188",
        orderNumber: "419399",
        datePlaced : "2021-10-01 10:19:23",
        dateMatched: "02-SEP-21 10.19.12.607098 AM",
        timeInForce: "0",
        bidPrice: "3.45",
        matchPrice: "3.45",
        volume: "800",
        status: "matched"

      ),

      buyHistoryModel(
          symbol: "ZSE.ZW",
          ticketNumber: "",
          orderNumber: "419399",
          datePlaced : "2021-10-01 10:19:23",
          dateMatched: "",
          timeInForce: "0",
          bidPrice: "3.45",
          matchPrice: "",
          volume: "800",
          status: "cancel"

      ),

      buyHistoryModel(
          symbol: "SIM.ZW",
          ticketNumber: "",
          orderNumber: "419399",
          datePlaced : "2021-10-01 10:19:23",
          dateMatched: "",
          timeInForce: "0",
          bidPrice: "3.45",
          matchPrice: "",
          volume: "800",
          status: "done"

      ),

    ];
    }
    }

然后在我的主檔案中，我將配接器中的專案添加到我的串列中

BuyHistoryAdapter pdb = new BuyHistoryAdapter();
    List<buyHistoryModel> tmpList = <buyHistoryModel>[];


    for(int i=0; i < pdb.getBuyHistory().length; i  ) {

      tmpList.add(pdb.getBuyHistory()[i]);

    }

但是如果從配接器檔案中觀察，狀態是不同的。在這個頁面上，我想要一個代碼來檢查狀態是否匹配。如果是，則添加到串列中，否則不添加到串列中。像這樣的東西

for(int i=0; i < pdb.getBuyHistory().length; i  ) {
        
          if(status == "matched"){
             tmpList.add(pdb.getBuyHistory()[i]);
          }
    
        }

這是完整的代碼

List<buyHistoryModel> buyHistoryList = [];
@override
  void initState() {
    BuyHistoryAdapter pdb = new BuyHistoryAdapter();
    List<buyHistoryModel> tmpList = <buyHistoryModel>[];

    for(int i=0; i < pdb.getBuyHistory().length; i  ) {
      tmpList.add(pdb.getBuyHistory()[i]);
    }
    setState(() {
      buyHistoryList = tmpList;
      _filteredList = buyHistoryList;
    });
    controller.addListener(() {
      if(controller.text.isEmpty) {
        setState(() {
          filter = "";
          _filteredList = buyHistoryList;
        });
      } else {
        setState(() {
          filter = controller.text;
        });
      }
    });
    super.initState();
  }

我怎么做？

uj5u.com熱心網友回復：

為什么你所有的變數都是字串？價格不應該是雙倍的，日期日期時間和狀態不應該是列舉嗎？反正你問的不是這個。對您的問題的最簡單答案是使用該.where()方法。因此，擺脫 for 回圈并在其位置執行以下操作：

BuyHistoryAdapter pdb = new BuyHistoryAdapter();
var originalList = pdb.getBuyHistory();
var matchedList = originalList.where((model) => model.status == 'matched').toList();

標籤：ios 扑 镖

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