how to remove data from List<map> message = [];-CodePudding

     [

       {
            "booking_no": "HC60398",
            "sender_name": "Tanvir",
            "receiver_name": "House",
            "sender_image": "image link",
            "receiver_image": "image link",
            "chat_id": "2",
            "message": "hlw",
            "files": [],
  
        },
        {
            "booking_no": "HC60398",
            "sender_name": "Tanvir",
            "receiver_name": "House",
            "sender_image": "image link",
            "receiver_image": "image link",
            "chat_id": "2",
            "message": "hi",
       
          
        },
        {
            "booking_no": "HC60399",
            "sender_name": "Tanvir",
            "receiver_name": "House",
            "sender_image": "image link",
            "receiver_image": "image link",
            "chat_id": "2",
            "message": "hlw",
            "files": [],
         
        },

      ]

how can I remove the same booking id data from the list, when I use contains its don't work cause, in this list only booking no are same but other value was different

CodePudding user response：

You can use this method to get your result:

List getNewListWithuotOccurencesBookingNo(List list) {
    Map map = {};
  for(int index  = 0; index < list.length; index  = 1) {
    final current = list[index];
    final id = current["booking_no"]; 
    if(map[id] != null){
      continue;
    }
    
    map[id] = current;
  }
  return map.values.toList();
}

print(getNewListWithuotOccurencesBookingNo(YourListHere));

change YourListHere with your list.

CodePudding user response：

final list= [

       {
            "booking_no": "HC60398",
            "sender_name": "Tanvir",
            "receiver_name": "House",
            "sender_image": "image link",
            "receiver_image": "image link",
            "chat_id": "2",
            "message": "hlw",
            "files": [],
  
        },
        {
            "booking_no": "HC60398",
            "sender_name": "Tanvir",
            "receiver_name": "House",
            "sender_image": "image link",
            "receiver_image": "image link",
            "chat_id": "2",
            "message": "hi",
       
          
        },
        {
            "booking_no": "HC60399",
            "sender_name": "Tanvir",
            "receiver_name": "House",
            "sender_image": "image link",
            "receiver_image": "image link",
            "chat_id": "2",
            "message": "hlw",
            "files": [],
         
        },

      ];
  
    final filterdList = [];
 
  for(final item in list){
    if (!filterdList.any((i) => i["booking_no"] == item["booking_no"])){
      filterdList.add(item);
    }
  }
  
  print(filterdList.length); // Output 2