【发布时间】：2017-11-27 23:47:23
【问题描述】：
这里是 JS 新手，已经为此苦苦挣扎了几个小时。
所以我创建了一个带有按钮的待办事项列表，该按钮将对象存储在 localStorage 内的数组中，还创建了带有内容和删除按钮的动态列表项。每当我单击删除按钮时，它都会删除动态列表项，但不会将其从 localStorage 中删除。我不知道如何将每个按钮分配给 localStorage 中的特定数组索引。
https://codepen.io/jupiterisland/pen/ooPXWV
var taskList = []; //build array
if(localStorage.taskList){ //call func to recreate li's on refresh
taskList = JSON.parse(localStorage.taskList) || [];
createTasks(taskList)
}
function submitFunc() {
var task = { //build objects
desc: document.getElementsByTagName("textarea")[0].value,
date: document.getElementsByTagName("input")[0].value,
time: document.getElementsByTagName("input")[1].value,
important: document.getElementsByTagName("input")[1].checked
};
if(task.desc && task.date !== ""){
taskList[taskList.length] = task; //put objects inside array
localStorage.taskList = JSON.stringify(taskList); //store array with stringify
newTaskList = JSON.parse(localStorage.taskList); //retrieve array with parse
createTasks(newTaskList)
document.getElementById("error").style.display = "none";
return false; //prevent submit
} else {
document.getElementById("error").style.display = "block";
document.getElementById("error").innerHTML = "Please enter a task description and a date.";
return false;
}
}
function createTasks (newTaskList){
for (i = 0; i < newTaskList.length; i++) { // display objects in list items
var currentTask = newTaskList[i];
var taskIndex = newTaskList.indexOf(currentTask);
newElement();
function newElement() {
var liNode = document.createElement("li");
var titleNode = document.createElement("h3");
var dNode = document.createElement("p");
var tNode = document.createElement("p");
var delNode = document.createElement("button")
liNode.className = "liNode";
titleNode.className = "titleNode";
dNode.className = "dNode";
tNode.className = "tNode";
delNode.className = "delete";
delNode.innerText = "Delete";
var titleText = newTaskList[i].desc;
var dateText = newTaskList[i].date;
var timeText = newTaskList[i].time;
var descNode = document.createTextNode(titleText);
var dateNode = document.createTextNode(dateText);
var timeNode = document.createTextNode(timeText);
titleNode.appendChild(descNode);
dNode.appendChild(dateNode);
tNode.appendChild(timeNode);
liNode.appendChild(titleNode);
liNode.appendChild(dNode);
liNode.appendChild(tNode);
liNode.appendChild(delNode);
document.getElementById("taskBoard").appendChild(liNode);
if (taskBoard.childElementCount > newTaskList.length) { //remove excess divs
for (n = 0; taskBoard.childElementCount - 2; n++) {
taskBoard.removeChild(taskBoard.firstChild);
}
}
function deleteTasks(){
var listItem = this.parentNode;
var ul = listItem.parentNode;
ul.removeChild(listItem);
}
delNode.addEventListener("click", deleteTasks);
}
}
}
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title>Document</title>
</head>
<body>
<h1>My Task Board</h1>
<div class="container">
<form onsubmit="return submitFunc()">
<div>
<label for="">Task:</label>
<textarea name="name" rows="8" cols="80"placeholder="Please enter your task description"></textarea>
</div>
<div>
<label for="">Deadline:</label>
<input type="date" placeholder="Choose a date">
<input type="time" placeholder="Set time">
</div>
<div>
<label for="">Important:</label>
<input type="checkbox" name="" value="">
</div>
<button type="submit" name="button">Add Task</button>
<div id="error"></div>
</form>
</div>
<div>
<ul id="taskBoard"></ul>
</div>
</body>
</html>【问题讨论】：
标签： javascript arrays dynamic local-storage