Javascript JSON 数组排序

Question

我正在尝试为减肥挑战应用程序构建自定义排序函数，当用户尝试单击第 1 周对以下 JSON 格式数据进行排序时，结果似乎不正确。 感谢您能否指导我在这里缺少的内容。 如果功能正常，我会将第 1 周更改为另一周。

 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"weeklyPercentageChange[0]"文字属性名称"weeklyPercentageChange[0]" - 也就是说，如果对象被定义为类似

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

这不是你所拥有的，这就是事情没有按预期工作的原因。

对于导航嵌套对象或数组以查找要排序的值的一般解决方案，请考虑传递一个回调，它会导航到要与之比较的嵌套值； 在这里， 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]); }