Javascript 未捕获类型错误:无法读取属性';长度';未定义的
我正在建立一个联系人列表,该列表按联系人姓氏的第一个字母分组 ajax请求成功后,联系人被推送到addContact: Ajax成功:Javascript 未捕获类型错误:无法读取属性';长度';未定义的,javascript,jquery,knockout.js,Javascript,Jquery,Knockout.js,我正在建立一个联系人列表,该列表按联系人姓氏的第一个字母分组 ajax请求成功后,联系人被推送到addContact: Ajax成功: ko.utils.arrayForEach(dataJS.contactList, function(c) { contactsModel.addContact(c); }); //add a contact in the right spot under the right letter contactsModel.addCo
ko.utils.arrayForEach(dataJS.contactList, function(c) {
contactsModel.addContact(c);
});
//add a contact in the right spot under the right letter
contactsModel.addContact = function(newContact) {
//grab first character
var firstLetter = (newContact.lname || "").charAt(0).toUpperCase();
//if it is a number use #
if (!isNaN(firstLetter)) {
firstLetter = "#";
}
//do we already have entries for this letter
if (!this.letterIndex[firstLetter]) {
//new object to track this letter's contacts
var letterContacts = {
letter: firstLetter,
contacts: ko.observableArray([])
};
this.letterIndex[firstLetter] = letterContacts; //easy access to it
//put the numbers at the end
if (firstLetter === "#") {
this.contactsByLetter.push(letterContacts);
} else {
//add the letter in the right spot
for (var i = 0, lettersLength = this.contactsByLetter().length; i < lettersLength; i++) {
var letter = this.contactsByLetter()[i].letter;
if (letter === "#" || firstLetter < letter) {
break;
}
}
this.contactsByLetter.splice(i, 0, letterContacts);
}
}
var contacts = this.letterIndex[firstLetter].contacts;
//now we have a letter to add our contact to, but need to add it in the right spot
var newContactName = newContact.lname + " " + newContact.fname;
for (var j = 0, contactsLength = contacts().length; j < contactsLength; j++) {
var contactName = contacts()[j].lName + " " + contacts()[j].fName;
if (newContactName < contactName) {
break;
}
}
//add the contact at the right index
contacts.splice(j, 0, newContact);
}.bind(contactsModel);
联系人模型。添加联系人:
ko.utils.arrayForEach(dataJS.contactList, function(c) {
contactsModel.addContact(c);
});
//add a contact in the right spot under the right letter
contactsModel.addContact = function(newContact) {
//grab first character
var firstLetter = (newContact.lname || "").charAt(0).toUpperCase();
//if it is a number use #
if (!isNaN(firstLetter)) {
firstLetter = "#";
}
//do we already have entries for this letter
if (!this.letterIndex[firstLetter]) {
//new object to track this letter's contacts
var letterContacts = {
letter: firstLetter,
contacts: ko.observableArray([])
};
this.letterIndex[firstLetter] = letterContacts; //easy access to it
//put the numbers at the end
if (firstLetter === "#") {
this.contactsByLetter.push(letterContacts);
} else {
//add the letter in the right spot
for (var i = 0, lettersLength = this.contactsByLetter().length; i < lettersLength; i++) {
var letter = this.contactsByLetter()[i].letter;
if (letter === "#" || firstLetter < letter) {
break;
}
}
this.contactsByLetter.splice(i, 0, letterContacts);
}
}
var contacts = this.letterIndex[firstLetter].contacts;
//now we have a letter to add our contact to, but need to add it in the right spot
var newContactName = newContact.lname + " " + newContact.fname;
for (var j = 0, contactsLength = contacts().length; j < contactsLength; j++) {
var contactName = contacts()[j].lName + " " + contacts()[j].fName;
if (newContactName < contactName) {
break;
}
}
//add the contact at the right index
contacts.splice(j, 0, newContact);
}.bind(contactsModel);
虽然这在JSFIDLE中起作用,但当我在本地尝试时,在第一次推送到addContact时,会出现以下错误:
Uncaught TypeError: Cannot read property 'length' of undefined
jQuery.jQuery.extend._Deferred.deferred.resolveWithjquery-1.5.1.js:869
donejquery-1.5.1.js:6591
jQuery.ajaxTransport.send.callbackjquery-1.5.1.js:7382
想法?谢谢对于循环和其他地方,您的语法在
中看起来是错误的,即()
用于调用函数。试着将你所有的contactsByLetter()
和contacts()
更改为contactsByLetter
和contacts
你的语法在循环和其他地方看起来是错误的,这就是调用函数的()
。尝试将您所有的contactsByLetter()
和contacts()
更改为contactsByLetter
和contacts
确保将绑定语句包装在jQuery ready中
$(function(){
ko.applyBindings(contactsModel, document.getElementById("view-panel-contacts"));
});
使用你在小提琴中提供的代码对我有效
确保将绑定语句包装在jQuery ready中
$(function(){
ko.applyBindings(contactsModel, document.getElementById("view-panel-contacts"));
});
使用你在小提琴中提供的代码对我有效
谢谢,但这似乎不管用。这是一把小提琴:我不明白的是,为什么它在小提琴中起作用,但对美沙克来说是错误的,但这似乎不起作用。这是一个提琴:我无法理解的是为什么它在提琴中工作,但在本地机器上,在var contacts=this.letterIndex[firstLetter].contacts之后,我会出错代码>执行控制台。记录(联系人)
并确保联系人是您尝试使用的正确对象。在本地计算机上,在var contacts=this.letterIndex[firstLetter]之后代码>执行console.log(contacts)
并确保contacts是您尝试使用的正确对象。