jQuery TypeError：数组索引未定义

Question

我有一些divs，需要将每个div 的数据存储在一个数组中。所以我使用了一个二维数组以下列方式存储这些数据。

this.saveBoardAndNotes = function (board_id, board_name) {
        var noteList = new Array(new Array());
        var self = this;
        var count = 0;

        $(".optimal-sticky-notes-sticker-note").each(function(){
            // Replace plain urls with links and improve html
            var note = $(this);
            var content = note.find(".textarea").html();
            var properties = JSON.stringify(self.getProperties(note));
            var noteID = note.attr("id");

            noteList[count]['content'] = content;
            noteList[count]['properties'] = properties;
            noteList[count]['noteID'] = noteID;

            count++;
        });

但是当我尝试在数组中存储多个 div 时，我在 firebug 中遇到以下错误

TypeError: noteList[count] is undefined

我该如何解决这个问题。顺便问一下，有没有优化的方法？提前致谢。

Answer 1

创建“二维”数组的方式对于此任务来说不是最佳的。您最好使用可以像这样创建的对象数组：

var noteList = [];
var self = this;
var count = 0;

$(".optimal-sticky-notes-sticker-note").each(function () {
    // Replace plain urls with links and improve html
    var note = $(this);
    var content = note.find(".textarea").html();
    var properties = JSON.stringify(self.getProperties(note));
    var noteID = note.attr("id");

    noteList[count] = {};
    noteList[count]['content'] = content;
    noteList[count]['properties'] = properties;
    noteList[count]['noteID'] = noteID;

    count++;
});

但是你真正需要的是使用$.fn.map:

var self = this;

var noteList = $(".optimal-sticky-notes-sticker-note").map(function () {
    // Replace plain urls with links and improve html
    var note = $(this);
    var content = note.find(".textarea").html();
    var properties = JSON.stringify(self.getProperties(note));
    var noteID = note.attr("id");

    return {
        content: content,
        properties: properties,
        noteID: noteID
    };
});

Answer 2

当你这样做时

var noteList = new Array(new Array());

你有一个数组数组。这很好，但您不能像使用对象一样设置属性值。而不是

noteList[count]['content'] = content;

你必须这样做

noteList[count].push(content);

如果你想推对象，你可以这样做

var myObj = {
'content' : content,
'properties' : properties,
'noteID' : noteID
};
noteList[count].push(myObj);

Answer 3

this.saveBoardAndNotes = function (board_id, board_name) {
        var noteList = [];
        var self = this;
        var count = 0;

        $(".optimal-sticky-notes-sticker-note").each(function(){
            // Replace plain urls with links and improve html
            var note = $(this);
            var content = note.find(".textarea").html();
            var properties = JSON.stringify(self.getProperties(note));
            var noteID = note.attr("id");

            noteList[count] = {};
            noteList[count]['content'] = content;
            noteList[count]['properties'] = properties;
            noteList[count]['noteID'] = noteID;

            count++;
        });