Question

我想知道为什么我的解决方案不起作用。我有以下内容：

//tells if type should be included in the row data
isInReport = {factual: true, eac: false, variance: false}

//report has hundreds of objects, each with a type of either Plan, Factual, EAC, Variance
report = [{type: "Plan"}, {type: "Factual"}, {type: "EAC"}, {type: "Variance"}];

我需要循环遍历报表数组，并且如果item.type是“Plan”，或者它是其他3种类型之一，但只有在isInReport对象中为true时，才会执行某些操作。因此，在我的示例中，如果item.type是“Plan”或“Factual”

，则if语句应该通过

为什么这段代码不起作用？即使有点奇怪，逻辑似乎也适合我。当我测试它时，无论如何都会返回所有类型。谢谢你的帮助！

report.map(function (item) {
  if (
  item.type === "Plan" ||
  item.type === (isInReport.factual) ? "Factual" : "Plan" ||
  item.type === (isInReport.eac) ? "EAC" : "Plan" ||
  item.type === (isInReport.variance) ? "Variance" : "Plan"
  ) {
   //do stuff
  }
});

Answer 1

你想做什么：

if ( item.type === "Plan" || isInReport[ item.type.toLowerCase() ] ) {
    //do stuff
}

有评论暗示这是不正确的。您能否确认报告中4个项目的结果？

//tells if type should be included in the row data
isInReport = {factual: true, eac: false, variance: false}

//report has hundreds of objects, each with a type of either Plan, Factual, EAC, Variance
report = [{type: "Plan"}, {type: "Factual"}, {type: "EAC"}, {type: "Variance"}];

report.forEach(function(item){
  if ( item.type === "Plan" || isInReport[ item.type.toLowerCase() ] ) {
    console.log("Item Type:" + item.type + " PASSED TEST");
  } else {
    console.log("Item Type:" + item.type + " FAILED TEST");
  }
});

如果您想坚持自己开始的方式，那么您希望使用一些括号来更好地控制顺序或操作。

//tells if type should be included in the row data
isInReport = {factual: true, eac: false, variance: false}

//report has hundreds of objects, each with a type of either Plan, Factual, EAC, Variance
report = [{type: "Plan"}, {type: "Factual"}, {type: "EAC"}, {type: "Variance"}];

report.forEach(function(item){
  if (
    item.type === "Plan" ||
    item.type === (isInReport.factual ? "Factual" : "Plan") ||
    item.type === (isInReport.eac ? "EAC" : "Plan") ||
    item.type === (isInReport.variance ? "Variance" : "Plan")
  ) {
    console.log("Item Type:" + item.type + " PASSED TEST");
  } else {
    console.log("Item Type:" + item.type + " FAILED TEST");
  }  
});

Answer 2

我没有看到错误...我在这里搞砸了：http://jsfiddle.net/Lnkky0fw/

$( document ).ready(function() {
var isInReport = {factual: true, eac: false, variance: false};

//report has hundreds of objects, each with a type of either Plan, Factual, EAC, Variance
var report = [{type: "Plan"},{type: "Factual"},{type: "EAC"},{type: "Variance"}];

report.map(function (item) {
  if (
  item.type === "Plan" ||
  item.type === (isInReport.factual) ? "Factual" : "Plan" ||
  item.type === (isInReport.eac) ? "EAC" : "Plan" ||
  item.type === (isInReport.variance) ? "Variance" : "Plan"
  ) {
   //do stuff
   alert('ok');

  }
});
});

Answer 3

您的“报告”中的元素之间缺少逗号。阵列。

Answer 4

我创建一个允许值的数组，然后使用过滤器。这将比多个嵌套的if / ternary混合物更容易阅读和维护。

＆＃13;

var isInReport = {
    factual: true,
    eac: false,
    variance: false
};

var report = [{ type: "Plan" }, { type: "Factual" }, { type: "EAC" }, { type: "Variance" }];

var allowed = ["plan"]
    .concat(Object.keys(isInReport)
    .map(function (key) {
        if (isInReport[key]) return key.toLowerCase();
    }).filter(function (v) {
        return v;
    })
);

var filtered = report.filter(function (d) {
    if (allowed.indexOf(d.type.toLowerCase()) > -1) return true;
    return false;
});

console.log(filtered);

＆＃13;

Answer 5

您需要将三元表达式括在括号中以获得预期结果

if (
  item.type === "Plan" ||
  item.type === ((isInReport.factual) ? "Factual" : "Plan") ||
  item.type === ((isInReport.eac) ? "EAC" : "Plan") ||
  item.type === ((isInReport.variance) ? "Variance" : "Plan")
  )

（你忘记了

中的逗号

report = [{type: "Plan"},{type: "Factual"},{type: "EAC"},{type: "Variance"}];）

如果语句测试多个三元运算符Javascript

5 个答案: