如何最小化打字稿功能以少花钱多办事

Question

我有这个功能：

private sectionIndex: number; <--- set above my constructor.

sections 对象的项目是：

public sections = {
  pi: [ **<-- Want to remove**
    {title: 'Employee Information'},
    {title: 'Address'},
    {title: 'Summary'},
  ],
  ee: [ **<-- Want to remove**
    {title: 'Employee Eligibility Information'},
    {title: 'Summary'},
  ],
  pd: [ **<-- Want to remove**
    {title: 'Payroll Information'},
    {title: 'Summary'},
  ],
  es: [ **<-- Want to remove**
    {title: 'Esignature'},
    {title: 'Summary'},
  ]
};

想这样合并：

public sections = {
  s: [
    {title: 'Employee Information'},
    {title: 'Address'},
    {title: 'Employee Eligibility Information'},
    {title: 'Summary'}, <-- Common between all...
    {title: 'Payroll Information'},
    {title: 'Esignature'}
  ]
};

这是我想要最小化的函数：

public somefunction() {

    let result = true;

    if (this.sectionIndex === this.sections.pi.length - 1 ||
      this.sectionIndex === this.sections.pd.length - 1 ||
      this.sectionIndex === this.sections.ee.length - 1 ||
      this.sectionIndex === this.sections.es.length - 1) {
      result = false;
      console.log('There are no more sections');
    } else {
      this.sectionIndex++;

    if (this.sections.pi.length - 1) {
        console.log('First section is ' + 
this.sections.pi[this.sectionIndex].title + ' which is ' + 
this.sections.pi[this.sectionIndex].value);
      } else if (this.sections.pd.length - 1) {
        console.log('First section is ' + 
this.sections.pd[this.sectionIndex].title + ' which is ' + 
this.sections.pd[this.sectionIndex].value);
      } else if (this.sections.pi.length - 1) {
        console.log('First section is ' + 
this.sections.ee[this.sectionIndex].title + ' which is ' + 
this.sections.ee[this.sectionIndex].value);
      } else if (this.sections.es.length - 1) {
        console.log('First section is ' + 
this.sections.es[this.sectionIndex].title + ' which is ' + 
this.sections.es[this.sectionIndex].value);
      }
    }
    return result;
 }

我想将上面的代码最小化为更可口的代码，而我不必执行 "OR's" if then else, else if's, blah, blah, blah...

此外，这些部分（目前是硬编码的）并不总是相同的。可能多，也可能少。

相似的是摘要部分。摘要将出现在所有部分

我的问题是，如何组合sections对象并删除仅使用子项遍历的"pi, ee, pd, and es?"？

Answer 1

要合并这些部分，您可以 flatten the object values。然后要删除重复项，您可以使用 set 保留已添加的条目：

const sections = {
  pi: [ 
    {title: 'Employee Information'},
    {title: 'Address'},
    {title: 'Summary'},
  ],
  ee: [ 
    {title: 'Employee Eligibility Information'},
    {title: 'Summary'},
  ],
  pd: [ 
    {title: 'Payroll Information'},
    {title: 'Summary'},
  ],
  es: [ 
    {title: 'Esignature'},
    {title: 'Summary'},
  ]
};

const combined = Object.values(sections).flat();
const addedTitles = new Set();
const noDuplicates = [];
combined.forEach(item => {
  if (!addedTitles.has(item.title)){
    noDuplicates.push(item);
    addedTitles.add(item.title)
  }
});

const result = { s: noDuplicates };
console.log(result);

如果您不希望列表很大，您可以使用 find 检查项目是否已经在列表中（不添加标题集）。类似于：

const combined = Object.values(sections).flat().reduce((result, item) => {
    if (!result.find(i => i.title === item.title)) {
        result.push(item);
    }
    return result;
}, []);

如何最小化打字稿功能以少花钱多办事

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