Javascript JSON数组排序

Question

我正在尝试为减肥挑战应用程序构建一个自定义排序函数，当用户试图点击第1周对以下JSON格式的数据进行排序时，结果似乎不正确。如果你能指导我在这里所缺少的东西，我将不胜感激。如果函数成功的话，我会把第一周改成另一周。

var array=[
{
"user": "Noah",
"weeklyPercentageChange":["10.37","-3.75","-2.21","-1.85","-1.68","-1.21","-1.41","-1.17","-0.47","-1.64","-23.36"  ]
},
{
"user": "Liam",
"weeklyPercentageChange":["-4.49","-2.61","-1.19","-0.36","-1.39","-1.29","-0.44","-0.22","-0.67","-0.33","-12.53"  ]
},
{
"user": "Mason",
"weeklyPercentageChange":["3.22","-2.40","0.35","-1.80","-0.25","-0.66","-2.42","0.00","1.71","-0.52","-9.00"  ]
},
{
"user": "Ethan",
"weeklyPercentageChange":["-1.31","0.00","-1.75","-0.78","0.61","-1.79","0.80","0.00","0.00","0.38","-3.75"]
},
{
"user": "Alexander",
"weeklyPercentageChange":["-1.26","0.00","-1.48","-1.50","-0.07","-1.66","-0.53","-0.20","0.00","-0.86","-7.42"]
},
{
"user": "Maria",
"weeklyPercentageChange":["-1.10","-1.90","-0.11","-0.63","2.52","-1.01","0.06","-0.06","-0.06","1.38","-0.94"  ]
},
{
"user": "Paul",
"weeklyPercentageChange":["1.08","-2.33","-0.10","-1.17","1.83","-1.70","-1.13","-0.19","0.00","0.00","-5.84"]
},
{
"user": "Steven",
"weeklyPercentageChange":["-0.77","-2.93","0.19","-1.22","-0.48","-1.39","-1.27","0.00","-0.23","-0.91","-8.84"  ]
},
{
"user": "Edward",
"weeklyPercentageChange":["-0.71","-1.73","1.46","-0.17","0.42","-1.23","-1.26","1.47","0.59","-2.81","-3.98"]
},
{
"user": "Benjamin",
"weeklyPercentageChange":["0.56","-0.28","0.80","-0.94","0.00","0.90","-0.05","1.17","-1.87","0.98","0.14"]
},
{
"user": "Zachary",
"weeklyPercentageChange":["-0.47","-1.29","0.48","-1.59","1.37","-2.65","-0.24","0.66","0.05","0.24","-3.41"]
},
{
"user": "Austin",
"weeklyPercentageChange":["-0.33","0.00","-3.05","-2.02","0.80","-1.48","1.58","-0.43","0.87","-1.90","-5.87"]
},
{
"user": "Jordan",
"weeklyPercentageChange":["0.06","-2.18","2.17","-0.56","0.84","-0.67","0.45","0.39","0.28","0.06","0.67"]
},
{
"user": "Gabriel",
"weeklyPercentageChange":["0.00","0.00","-0.12","-0.81","0.25","0.00","0.00","0.00","0.00","0.00","-0.68"]
},
{
"user": "Wayne",
"weeklyPercentageChange":["0.20","-3.45","0.35","0.49","0.56","0.00","-0.61","0.54","0.54","-0.41","-1.83"]
},
{
"user": "Willie",
"weeklyPercentageChange":["-0.83","-3.21","0.71","0.00","-1.05","0.35","0.07","0.14","-0.07","-1.45","-3.72"]
},
{
"user": "Frank",
"weeklyPercentageChange":["0.00","0.00","-3.04","0.88","1.37","-0.41","-1.21","2.10","0.00","-0.58","-0.94"]
}
];
function GetSortOrder(prop){
return function(a,b){
if( a[prop] > b[prop]){
return 1;
}else if( a[prop] < b[prop] ){
return -1;
}
return 0;
}
}
/* array.sort( GetSortOrder("user") );
document.write("Sorted User Names : <br>");
for (var item in array) {
document.write("<br>"+array[item].user);
} */
array.sort( GetSortOrder("weeklyPercentageChange[0]") );
document.write("<br><br> Sorted Weekly Percentage Change : <br>");
for (var item in array) {
document.write("<br>"+array[item].weeklyPercentageChange[0]);
}

Answer 1

GetSortOrder("weeklyPercentageChange[0]")将导致查找文字属性名称"weeklyPercentageChange[0]"，也就是说，如果对象被定义为类似的东西

{
user: 'name',
'weeklyPercentageChange[0]': 55
}

这不是你所拥有的，这就是为什么事情没有按预期进行。

对于导航嵌套对象或数组以查找排序依据的值的通用解决方案，请考虑传递回调，该回调将导航到要进行比较的嵌套值；这里是obj => obj.weeklyPercentageChange[0]。

您还可以通过简单地返回值之间的差异来使代码更加简洁：

var array=[{user:"Noah",weeklyPercentageChange:["10.37","-3.75","-2.21","-1.85","-1.68","-1.21","-1.41","-1.17","-0.47","-1.64","-23.36"]},{user:"Liam",weeklyPercentageChange:["-4.49","-2.61","-1.19","-0.36","-1.39","-1.29","-0.44","-0.22","-0.67","-0.33","-12.53"]},{user:"Mason",weeklyPercentageChange:["3.22","-2.40","0.35","-1.80","-0.25","-0.66","-2.42","0.00","1.71","-0.52","-9.00"]},{user:"Ethan",weeklyPercentageChange:["-1.31","0.00","-1.75","-0.78","0.61","-1.79","0.80","0.00","0.00","0.38","-3.75"]},{user:"Alexander",weeklyPercentageChange:["-1.26","0.00","-1.48","-1.50","-0.07","-1.66","-0.53","-0.20","0.00","-0.86","-7.42"]},{user:"Maria",weeklyPercentageChange:["-1.10","-1.90","-0.11","-0.63","2.52","-1.01","0.06","-0.06","-0.06","1.38","-0.94"]},{user:"Paul",weeklyPercentageChange:["1.08","-2.33","-0.10","-1.17","1.83","-1.70","-1.13","-0.19","0.00","0.00","-5.84"]},{user:"Steven",weeklyPercentageChange:["-0.77","-2.93","0.19","-1.22","-0.48","-1.39","-1.27","0.00","-0.23","-0.91","-8.84"]},{user:"Edward",weeklyPercentageChange:["-0.71","-1.73","1.46","-0.17","0.42","-1.23","-1.26","1.47","0.59","-2.81","-3.98"]},{user:"Benjamin",weeklyPercentageChange:["0.56","-0.28","0.80","-0.94","0.00","0.90","-0.05","1.17","-1.87","0.98","0.14"]},{user:"Zachary",weeklyPercentageChange:["-0.47","-1.29","0.48","-1.59","1.37","-2.65","-0.24","0.66","0.05","0.24","-3.41"]},{user:"Austin",weeklyPercentageChange:["-0.33","0.00","-3.05","-2.02","0.80","-1.48","1.58","-0.43","0.87","-1.90","-5.87"]},{user:"Jordan",weeklyPercentageChange:["0.06","-2.18","2.17","-0.56","0.84","-0.67","0.45","0.39","0.28","0.06","0.67"]},{user:"Gabriel",weeklyPercentageChange:["0.00","0.00","-0.12","-0.81","0.25","0.00","0.00","0.00","0.00","0.00","-0.68"]},{user:"Wayne",weeklyPercentageChange:["0.20","-3.45","0.35","0.49","0.56","0.00","-0.61","0.54","0.54","-0.41","-1.83"]},{user:"Willie",weeklyPercentageChange:["-0.83","-3.21","0.71","0.00","-1.05","0.35","0.07","0.14","-0.07","-1.45","-3.72"]},{user:"Frank",weeklyPercentageChange:["0.00","0.00","-3.04","0.88","1.37","-0.41","-1.21","2.10","0.00","-0.58","-0.94"]}];
const GetSortOrder = getProp => (a,b) => getProp(a) - getProp(b);
array.sort( GetSortOrder(obj => obj.weeklyPercentageChange[0]) );
document.write("<br><br> Sorted Weekly Percentage Change : <br>");
for (var item in array) {
document.write("<br>"+array[item].weeklyPercentageChange[0]);
}