Question

这是codeacademy项目的一部分。从开头到列表的部分（）;功能或多或少都有效。我的任务是使用for循环创建搜索功能。提前谢谢。

var bob = {
    firstName: "Bob",
    lastName: "Jones",

    phoneNumber: "(650) 777 - 7777",
    email: "bob.jones@example.com"
};

var mary = {
    firstName: "Mary",
    lastName: "Johnson",

    phoneNumber: "(650) 888 - 8888",
    email: "mary.johnson@example.com"
};

var contacts = [bob, mary];

function printPerson (person) {
    console.log(person.firstName + " " + person.lastName);
}

var list =  function(){
    var contactsNumber = contacts.length;
    for(i=0; i<=contactsNumber; i++){
        printPerson(contacts[i]);
    }
};

list();

var search = function(lastName){
    var number = contacts.length;
    for(i=0; i<= number; i++){
        if(lastName === contacts[i].lastName){
            printPerson(contacts[i]);
        }
    }
};

search("Jones");

Answer 1

如果数组中有2个项目，则需要循环索引0和1，而不 2。因此，请使用<代替<=：

for(var i = 0; i < number; i++)

Answer 2

该练习被窃听（或者不知道是否修复了它）你必须运行所有其他功能才能使其正确：

var bob = {
    firstName: "Bob",
    lastName: "Jones",

    phoneNumber: "(650) 777 - 7777",
    email: "bob.jones@example.com"
};

var mary = {
    firstName: "Mary",
    lastName: "Johnson",

    phoneNumber: "(650) 888 - 8888",
    email: "mary.johnson@example.com"
};

var contacts = [bob, mary];

function printPerson (person) {
    console.log(person.firstName + " " + person.lastName);
}

var list = function ()
{
    var contactsNum = contacts.length;
    for (i=0; i < contactsNum; i++)
    printPerson(contacts[i]);
};

function search(lastName){
     var items = contacts.length;
     for(i = 0; i < items; i++){
         if(contacts[i].lastName == lastName)
              printPerson(contacts[i]);      
     }
}
list();
search("Jones");

Answer 3

由于您使用了var个关键字，因此无法访问该功能中的联系人。在联系人之前移除var关键字，它应该可以正常工作。

Answer 4

var personList = [
    { 'FirstName' : "John", 'LastName': "Doe"},
    { 'FirstName' : "Jane", 'LastName': "Deen"}
]


function PersonSearchService() {  
  this.Print = function(person) {
     console.log(person.FirstName + " " + person.LastName);
  }  
  this.Search = function(lastName) {
      for(var p in personList) {         
         if(personList[p].LastName === lastName) {             
             this.Print (personList[p]);
         }
      }
  }
}

var p = new PersonSearchService();
p.Search ("Doe");

你可以试试这种方式

search（）使用for循环。

4 个答案: