比较两个数组时无法正确找到重复项答案

【问题标题】：Cannot find duplicates properly while comparing two arrays比较两个数组时无法正确找到重复项
【发布时间】：2020-01-29 21:35:28
【问题描述】：

我有两个Array 的问题。我必须比较才能仅在必要时创建，否则更新。

这是我的代码：

const issueList = [
  "Ajout de google analytics",
  "Déployement en continue dev",
  "Déployement en continue préproduction",
  "Déployement en continue production",
  "Déployment ipa automatique sur app store",
  "Déployment apk automatique sur play store"
];

const existingIssueList = [
  "Déployement en continue production",
  "Déployement en continue préproduction",
  "List swipe web"
];

for (let i = 0; i < issueList.length; i += 1) {
  let issueFound = null;
  for (let j = 0; j < existingIssueList.length; j += 1) {
    if (issueList[i] === existingIssueList[j]) {
      issueFound = existingIssueList[j];
      break;
    }
  }
  
  // If issue was found, we do not need to create theissue
  let issue;
  if (issueFound) {
    issue = updateIssue({
      issue: issueFound,
    });
    console.log(`issue has been updated`);
  } else {
    issue = createIssue({
      issue: issueList[i],
    });
    console.log(`issue has been created`);
  }
}

function updateIssue(){}
function createIssue(){}

我希望找到重复的值并更新它们，我在哪里失败了？

【问题讨论】：

会发生什么？请添加想要的结果。
如果您必须经常在长数组中查找字符串，请改用Set，因为它查找速度很快。

标签： javascript arrays node.js compare

【解决方案1】：

您的逻辑似乎很复杂，请检查您是否可以使用以下逻辑：

    for (let i = 0; i < issueList.length; i += 1) {
       if(existingIssueList.indexOf(issueList[i]) > -1) {
          //Issue already exists
       }else {
         //Create Issue 
       }
    }

希望对你有所帮助。

【讨论】：

【解决方案2】：

lodash 可能会有所帮助，例如

_.filter(issueList, (val, i, iteratee) => _.includes(iteratee, val, i + 1));

【讨论】：

【解决方案3】：

出于可读性原因，我添加了includes。记录创建/更新了哪个问题后，您的代码似乎可以正常工作：

const issueList = [
  "Requetes de création de table commerçant",
  "Déployment apk automatique sur play store"
];

const existingIssueList = [
  "Déployment apk automatique sur play store",
  "Déployment ipa automatique sur app store",
  "Déployement en continue production",
  "Déployement en continue préproduction"
];

for (let i = 0; i < issueList.length; i += 1) {
  let issueFound = existingIssueList.includes(issueList[i]);
  
  // If issue was found, we do not need to create theissue
  let issue;
  if (issueFound) {
    issue = updateIssue({
      issue: issueFound,
    });
    console.log(`issue has been updated: ` + issueList[i]);
  } else {
    issue = createIssue({
      issue: issueList[i],
    });
    console.log(`issue has been created: ` + issueList[i]);
  }
}

function updateIssue(){}
function createIssue(){}

【讨论】：

【解决方案4】：

const issueList = [
  "Déployement en continue dev",
  "Déployement en continue préproduction",
  "Déployement en continue production",
  "Déployment ipa automatique sur app store",
  "Déployment apk automatique sur play store"
];

const existingIssueList = [
  "Déployment apk automatique sur play store",
  "Déployment ipa automatique sur app store"
];

let issueFoundIndex = issueList.forEach(issue => {
    const existingIssueListIndex = existingIssueList.findIndex(x => x === issue);

    if(existingIssueListIndex !== -1){
      console.log('Found issue:' + existingIssueList[existingIssueListIndex]);
    }        

    const mutatedIssue = existingIssueListIndex !== -1
      ? updateIssue(existingIssueList[existingIssueListIndex])
      : createIssue(issue);
    console.log(mutatedIssue);
});

function updateIssue(issue){ return issue; }
function createIssue(issue){ return issue; }

【讨论】：