判断数组对象中是否有某个对象有值

时间 2020-12-20
<!DOCTYPE html>
<html lang="en"> 
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
    <script>
        var arr = [
            {
                "id": "111",
                "adjustState": "已读取"
            },
            {
                "id": "222",
                "adjustState": "未读取"
            }
        ]; 
        function changeAdjustState(id, adjustState) {
            var item = {
                "id": id,
                "adjustState": adjustState
            }
            if (arr.length > 0) {
                var res = this.findElem(arr, "id", id); 
                if (res != "-1") {
                    arr.splice(res, 1, item); //替换值，如果数组有这个id存在，再次修改的时候覆盖原来的值
                } else {
                    arr.push(item);
                }
            } else {
                arr.push(item);
            }
        };
        //判断数组对象中是否有某个值
        function findElem(arrayToSearch, attr, val) {
            //debugger
            for (var i = 0; i < arrayToSearch.length; i++) {
                if (arrayToSearch[i][attr] == val) {
                    return i; //返回当前索引值
                }
            }
            return -1;
        };

        this.changeAdjustState("111", "已读取111");
        this.changeAdjustState("222", "已读取222");
        this.changeAdjustState("333", "已读取333");
        this.changeAdjustState("444", "已读取444");
        console.log(arr); 
    </script>
</head> 
<body> 
</body> 
</html>
输出结果：