錯誤型別錯誤：無法讀取null的屬性（讀取“toISOString”）

我最近將 package.json 中的依賴項升級到最新版本。依賴項已過時至少 2 年或更長時間。每當我訪問正在呼叫此資料的頁面時，都會收到此錯誤。我認為問題可能與更新的依賴項及其新功能有關。這是什么原因？

這是錯誤中參考的代碼部分

this.miceBirthdayFilter = (calendarDate: Date): boolean => {
      let birthDates = [];
      this.uniqueValuesForEachAttribute['subject_birth_date'].forEach(date => {
        birthDates.push(date);
      });
      console.log("miceBirthdayFilter in Session "   birthDates.length)
      console.log("calendarDate in miceBirthdayFilter in Session "   calendarDate)
      return birthDates.includes(calendarDate.toISOString().substring(0, 10));
    };

這是更新后的 package.json

{
  "name": "pipeline-viewer",
  "version": "0.0.0",
  "scripts": {
    "ng": "ng",
    "start": "ng serve",
    "build": "ng build",
    "test": "ng test",
    "lint": "ng lint",
    "e2e": "ng e2e"
  },
  "private": true,
  "dependencies": {
    "@angular/animations": "^12.0.0",
    "@angular/cdk": "^12.0.0",
    "@angular/common": "^12.0.0",
    "@angular/compiler": "^12.0.0",
    "@angular/core": "^12.0.0",
    "@angular/flex-layout": "^12.0.0-beta.35",
    "@angular/forms": "^12.0.0",
    "@angular/material": "^12.0.0",
    "@angular/material-moment-adapter": "^12.0.0",
    "@angular/platform-browser": "^12.0.0",
    "@angular/platform-browser-dynamic": "^12.0.0",
    "@angular/router": "^12.0.0",
    "@wizpanda/super-gif": "0.0.5",
    "angular-plotly.js": "^4.0.4",
    "bootstrap": "^5.1.3", 
    "moment": "^2.29.1",
    "plotly.js": "^2.5.1",
    "rxjs": "^7.4.0",
    "rxjs-compat": "^6.6.7",
    "zone.js": "^0.11.4"
  },
  "devDependencies": {
    "@angular-devkit/build-angular": "^12.0.0",
    "@angular/cli": "^12.0.0",
    "@angular/compiler-cli": "^12.0.0"
  }
}

這是顯示圖形和圖表的舊 package.json。

{
  "name": "pipeline-viewer",
  "version": "0.0.0",
  "scripts": {
    "ng": "ng",
    "start": "ng serve",
    "build": "ng build",
    "test": "ng test",
    "lint": "ng lint",
    "e2e": "ng e2e"
  },
  "private": true,
  "dependencies": {
    "@angular/animations": "^7.1.4",
    "@angular/cdk": "^7.3.7",
    "@angular/common": "~7.1.0",
    "@angular/compiler": "~7.1.0",
    "@angular/core": "~7.1.0",
    "@angular/flex-layout": "^7.0.0-beta.24",
    "@angular/forms": "~7.1.0",
    "@angular/material": "^7.3.3",
    "@angular/material-moment-adapter": "^8.1.2",
    "@angular/platform-browser": "~7.1.0",
    "@angular/platform-browser-dynamic": "~7.1.0",
    "@angular/router": "~7.1.0",
    "@wizpanda/super-gif": "0.0.5",
    "angular-plotly.js": "^1.3.2",
    "bootstrap": "^4.2.1",
    "moment": "^2.24.0",
    "plotly.js": "^1.49.0",
    "rxjs": "~6.3.3",
    "rxjs-compat": "^6.3.3",
    "zone.js": "~0.8.26"
  },
  "devDependencies": {
    "@angular-devkit/build-angular": "~0.11.0",
    "@angular/cli": "~7.1.3",
    "@angular/compiler-cli": "~7.1.0"
  }
}

uj5u.com熱心網友回復：

錯誤告訴您傳遞給函式的值null在您的代碼中至少出現一次。TypeError: Cannot read properties of null (reading 'toISOString')

您能否通過在您的函式中添加一些提前退出來仔細檢查這一點。像這樣的東西。

this.miceBirthdayFilter = (calendarDate: Date): boolean => {
      let birthDates = [];
      
      // If calendarDate is null, return false.
      if (!calendarDate) {
        return false 
      }  

      return birthDates.includes(calendarDate.toISOString().substring(0, 10));
    };

uj5u.com熱心網友回復：

return (calendarDate == null ? true :birthDates.includes(calendarDate.toISOString().split('T'))) 這解決了這個問題

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