的forEach與在

Question

我有幾件事情我想用foreach取代（這是一類我正在要求），但是他們沒有一個人工作：

我最初對於代碼（此作品正確顯示內容）：

for (var i in education.schools) { 
     $('#education').append(HTMLschoolStart); 

     var formattedName = HTMLschoolName.replace('%data%', education.schools[i].name).replace('#', education.schools[i].url); 
     var formattedLocation = HTMLschoolLocation.replace('%data%', education.schools[i].location); 
     var formattedDegree = HTMLschoolDegree.replace('%data%', education.schools[i].degree); 
     var formattedMajors = HTMLschoolMajor.replace('%data%', education.schools[i].majors); 
     var formattedDates = HTMLschoolDates.replace('%data%', education.schools[i].dates); 
     var formattedNameDegree = formattedName + formattedDegree; 


     $('.education-entry:last').append(formattedNameDegree); 
     $('.education-entry:last').append(formattedDates); 
     $('.education-entry:last').append(formattedLocation); 
     $('.education-entry:last').append(formattedMajors); 
    } 

我的forEach變化（不顯示任何內容，所有內容將消失）：

education.schools.forEach(function() { 
     $('#education').append(HTMLschoolStart); 

     var formattedName = HTMLschoolName.replace('%data%', education.schools[i].name).replace('#', education.schools[i].url); 
     var formattedLocation = HTMLschoolLocation.replace('%data%', education.schools[i].location); 
     var formattedDegree = HTMLschoolDegree.replace('%data%', education.schools[i].degree); 
     var formattedMajors = HTMLschoolMajor.replace('%data%', education.schools[i].majors); 
     var formattedDates = HTMLschoolDates.replace('%data%', education.schools[i].dates); 
     var formattedNameDegree = formattedName + formattedDegree; 


     $('.education-entry:last').append(formattedNameDegree); 
     $('.education-entry:last').append(formattedDates); 
     $('.education-entry:last').append(formattedLocation); 
     $('.education-entry:last').append(formattedMajors); 
    }) 

第二個是一個if語句，我應該更換的一部分與forEach。

if語句工作正常，像這樣唯一的問題是它只有整整7個項目好，如果我再添加到陣列我也將必須更新此：

if (bio.skills.length > 0) { 
     $('#header').append(HTMLskillsStart); 

     var formattedSkill = HTMLskills.replace('%data%', bio.skills[0]); 
     $('#skills').append(formattedSkill); 
     var formattedSkill = HTMLskills.replace('%data%', bio.skills[1]); 
     $('#skills').append(formattedSkill); 
     var formattedSkill = HTMLskills.replace('%data%', bio.skills[2]); 
     $('#skills').append(formattedSkill); 
     var formattedSkill = HTMLskills.replace('%data%', bio.skills[3]); 
     $('#skills').append(formattedSkill); 
     var formattedSkill = HTMLskills.replace('%data%', bio.skills[4]); 
     $('#skills').append(formattedSkill); 
     var formattedSkill = HTMLskills.replace('%data%', bio.skills[5]); 
     $('#skills').append(formattedSkill); 
     var formattedSkill = HTMLskills.replace('%data%', bio.skills[6]); 
     $('#skills').append(formattedSkill); 
    } 

foreach循環碼（代替陣列中顯示每個項目的它顯示陣列中的所有項目七次，基本上它似乎來遍歷它的正確的次數，但所有7項輸出到每次迭代）：

if (bio.skills.length > 0) { 
     $('#header').append(HTMLskillsStart); 

     bio.skills.forEach(function(){ 
      var formattedSkill = HTMLskills.replace('%data%', bio.skills); 
      $('#skills').append(formattedSkill); 
     }) 
    } 

Answer 1

嘗試聲明中的索引210的回調函數：

education.schools.forEach(function(val, i) { 
    $('#education').append(HTMLschoolStart); 

    var formattedName = HTMLschoolName.replace('%data%', education.schools[i].name).replace('#', education.schools[i].url); 
    var formattedLocation = HTMLschoolLocation.replace('%data%', education.schools[i].location); 
    var formattedDegree = HTMLschoolDegree.replace('%data%', education.schools[i].degree); 
    var formattedMajors = HTMLschoolMajor.replace('%data%', education.schools[i].majors); 
    var formattedDates = HTMLschoolDates.replace('%data%', education.schools[i].dates); 
    var formattedNameDegree = formattedName + formattedDegree; 


    $('.education-entry:last').append(formattedNameDegree); 
    $('.education-entry:last').append(formattedDates); 
    $('.education-entry:last').append(formattedLocation); 
    $('.education-entry:last').append(formattedMajors); 
}); 

每Mozilla：

回調調用與三個參數：

• 元素值

• 元素索引

• 陣列正被遍歷

EDIT：

如Andreas評價提到，如果forEach運行關閉education.schools陣列，那麼可以使用所述第一參數（val）在回調中代替education.schools[i]獲取當前項目。

Answer 2

的每個回調得到三個參數傳遞：

• CurrentValue的 - 陣列中的當前元素
• 索引 - 所述ucrrent值
• 陣列的索引 - 的陣列本身

所以你應該使用currentValue.url而不是education.schools[i].name。

education.schools.forEach(function(currentValue) { 
    $('#education').append(HTMLschoolStart); 

    var formattedName = HTMLschoolName.replace('%data%', currentValue.name).replace('#', currentValue.url); 
    var formattedLocation = HTMLschoolLocation.replace('%data%', currentValue.location); 
    var formattedDegree = HTMLschoolDegree.replace('%data%', currentValue.degree); 
    var formattedMajors = HTMLschoolMajor.replace('%data%', currentValue.majors); 
    var formattedDates = HTMLschoolDates.replace('%data%', currentValue.dates); 
    var formattedNameDegree = formattedName + formattedDegree; 


    $('.education-entry:last').append(formattedNameDegree); 
    $('.education-entry:last').append(formattedDates); 
    $('.education-entry:last').append(formattedLocation); 
    $('.education-entry:last').append(formattedMajors); 
}) 

Answer 3

您forEach中的問題是您沒有定義i。要解決這個問題，您應該替換現有變量的i，或者定義i。

你的代碼可能是這樣的：

education.schools.forEach(function() { 
    $('#education').append(HTMLschoolStart); 

    var formattedName = HTMLschoolName.replace('%data%', this.name).replace('#', this.url); 
    var formattedLocation = HTMLschoolLocation.replace('%data%', this.location); 
    var formattedDegree = HTMLschoolDegree.replace('%data%', this.degree); 
    var formattedMajors = HTMLschoolMajor.replace('%data%', this.majors); 
    var formattedDates = HTMLschoolDates.replace('%data%', this.dates); 
    var formattedNameDegree = formattedName + formattedDegree; 


    $('.education-entry:last').append(formattedNameDegree); 
    $('.education-entry:last').append(formattedDates); 
    $('.education-entry:last').append(formattedLocation); 
    $('.education-entry:last').append(formattedMajors); 
}) 

注意，主要的變化是採用this代替education.schools[i]。