我想从div中保存和恢复数据 - 这是其他div的容器，
为了实现它，我使用本地存储和JSON：
window.onload = restoreJason;
function makeJson(){
var canvas = document.getElementById("canvas");
var shapes = canvas.querySelectorAll("div[class='drag']");
var divs = new Object();
for(var i=0; i<shapes.length; ++i){
divs[shapes[i].getAttribute('innerHTML')] = shapes[i].innerHTML;
}
localStorage.setItem("divs", JSON.stringify(divs));
}
function restoreJason(){
var divs = JSON.parse(localStorage.getItem("divs"));
var canvas = document.getElementById("canvas");
var shapes = canvas.querySelectorAll("div[class='drag']");
for(var i = 0; i<shapes.length; i++){
shapes[i].value = divs[shapes[i].getAttribute("innerHTML")];
}
console.log(divs);
}
但是，我不知道如何访问元素的innerHTML并保存或恢复它。
你认为我会做什么？
（更详细一点 - 我需要在用户点击“保存”时保存div的内容，并在用户点击“加载”时加载它。这是最常见的...）
注意：“画布”只是主div的id，而不是真正的“画布”。
function randomizeColor() {
var letters = '0123456789ABCDEF';
var color = '#';
for (var i = 0; i < 6; i++) {
color += letters[Math.floor(Math.random() * letters.length)];
}
return color;
}
function randomizeRectangle() {
var width = Math.random() * 700 + 50;
var height = Math.random() * 250 + 50;
if (height <= 20) {
height = 20;
}
var posX = Math.round(Math.random() * window.innerWidth);
var posY = Math.round(Math.random() * window.innerHeight);
var randomRecObj = {
"width": width + "px",
"height": height + "px",
"posX": posX,
"posY": posY
};
return randomRecObj;
}
function makeShape() {
var rect = randomizeRectangle();
var rectDOM = document.createElement("div");
rectDOM.className = "rectangle";
rectDOM.style.border = "1px solid black";
rectDOM.style.width = rect.width;
rectDOM.style.height = rect.height;
rectDOM.style.background = randomizeColor();
rectDOM.style.top = rect.posY + "px";
rectDOM.style.left = rect.posX + "px";
//rectDOM.addEventListener("click", selectShape);
// rectDOM.style.transform =rect.rotation;
return rectDOM;
}
function randRect() {
var rectDOM = makeShape();
var canvas = document.getElementById("canvas");
canvas.appendChild(rectDOM);
}
function randOval() {
var ovalDOM = makeShape();
ovalDOM.style.borderRadius = "50%";
var canvas = document.getElementById("canvas");
canvas.appendChild(ovalDOM);
}
function changeColor(){
}
function cancelSelection() {
var selected = document.getElementsByClassName("selected");
while (selected) {
selected[0].classList.remove(selected[0]);
}
}
function removeShape(event) {
var selectedShapes = document.getElementsByClassName("selected");
var len = selectedShapes.length;
while (len > 0) {
selectedShapes[0].parentNode.removeChild(selectedShapes[0]);
--len;
}
}
function removeCorners(rectDom) {
var corners = document.getElementsByClassName("corners");
var len = corners.length;
while (len > 0) {
corners[0].classList.remove("corners");
--len;
}
}.header{
background: #4ABDAC;
color: #fff;
margin: 1px;
}
hr{
border-top: 3px double #2a3132;
}
ul{
list-style: none;
margin: 0;
padding: 0;
overflow: hidden;
background-color: #90afc5;
}
li{
float: left;
border: 2px solid #336b87;
padding: 3px;
margin: 3px;
}
li>a{
display: block;
color: #2a3132;
text-decoration: none;
padding: 10px 14px;
}
#color{
margin-left: 150px;
}
#rect{
margin-left: 100px;
}
li>a:hover{
color: #763626;
cursor: pointer;
}
#canvas{
background: #66a5ad;
position: relative;
height: 1200px;
width: 100%;
}
.corners{
position: absolute;
height: 10px;
width: 10px;
background:#fff;
border: 1px solid black;
display: none;
}
.selected .corners{
display: inline-block;
}
.cornerUpLeft{
top: -5px;
left: -5px;
}
.cornerUpRight{
top: -5px;
right: -5px;
}
.cornerBtmLeft{
bottom: -5px;
left: -5px;
}
.cornerBtmRight{
bottom: -5px;
right: -5px;
}
.rectangle{
position: absolute;
}
.colorBox{
border: 1px solid black;
height: 20px;
width: 20px;
list-style: none;
}<!DOCTYPE html>
<html lang="en">
<head>
<title>Sketch Board - Eyal Segal Project</title>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
<link href="css/style.css" rel="stylesheet">
<script src="js/sketch.js"></script>
</head>
<body>
<h1 class="header">Sketch Board</h1>
<div>
<ul class="toolbar">
<li><a>Load</a></li>
<li id="Save"><a>Save</a></li>
<li id="rect"><a onclick="randRect()">Rectangle</a></li>
<li><a onclick="randOval()">Oval</a></li>
</ul>
<hr>
</div>
<div class="canvas" id="canvas">
</div>
</body>
</html>
答案 0 :(得分：0)
您需要做的就是将.innerHTML的{{1}}设置为div id="canvas"。根本不需要JSON或循环。
此外，请勿使用内联HTML事件属性（localStorage）。相反，使用基于标准的现代事件处理单独执行所有JavaScript。
最后，onclick元素无需响应点击事件。实际上，您的<a>元素无效，因为它们无论如何都没有a或name属性。可以简单地为点击事件设置href个元素。
这是执行此操作的代码，但它不会在Stack Overflow代码段环境中执行，但您可以看到它正在运行 here 。
li// Get reference to the "canvas"
var can = document.getElementById("canvas");
// Save the content of the canvas to localStorage
function saveData(){
localStorage.setItem("canvas", can.innerHTML);
}
// Get localStorage data
function restoreData(){
can.innerHTML = localStorage.getItem("canvas");
}
// get load and save references
var load = document.getElementById("load");
var save = document.getElementById("save");
// Set up event handlers
load.addEventListener("click", restoreData);
save.addEventListener("click", saveData);
// Get references to the rect and oval "buttons" and set their event handlers
var rect = document.getElementById("rect");
rect.addEventListener("click", randRect);
var oval = document.getElementById("oval");
oval.addEventListener("click", randOval);
function randomizeColor() {
var letters = '0123456789ABCDEF';
var color = '#';
for (var i = 0; i < 6; i++) {
color += letters[Math.floor(Math.random() * letters.length)];
}
return color;
}
function randomizeRectangle() {
var width = Math.random() * 700 + 50;
var height = Math.random() * 250 + 50;
if (height <= 20) {
height = 20;
}
var posX = Math.round(Math.random() * window.innerWidth);
var posY = Math.round(Math.random() * window.innerHeight);
var randomRecObj = {
"width": width + "px",
"height": height + "px",
"posX": posX,
"posY": posY
};
return randomRecObj;
}
function makeShape() {
var rect = randomizeRectangle();
var rectDOM = document.createElement("div");
rectDOM.className = "rectangle";
rectDOM.style.border = "1px solid black";
rectDOM.style.width = rect.width;
rectDOM.style.height = rect.height;
rectDOM.style.background = randomizeColor();
rectDOM.style.top = rect.posY + "px";
rectDOM.style.left = rect.posX + "px";
//rectDOM.addEventListener("click", selectShape);
// rectDOM.style.transform =rect.rotation;
return rectDOM;
}
function randRect() {
var rectDOM = makeShape();
var canvas = document.getElementById("canvas");
canvas.appendChild(rectDOM);
}
function randOval() {
var ovalDOM = makeShape();
ovalDOM.style.borderRadius = "50%";
var canvas = document.getElementById("canvas");
canvas.appendChild(ovalDOM);
}
function changeColor(){
}
function cancelSelection() {
var selected = document.getElementsByClassName("selected");
while (selected) {
selected[0].classList.remove(selected[0]);
}
}
function removeShape(event) {
var selectedShapes = document.getElementsByClassName("selected");
var len = selectedShapes.length;
while (len > 0) {
selectedShapes[0].parentNode.removeChild(selectedShapes[0]);
--len;
}
}
function removeCorners(rectDom) {
var corners = document.getElementsByClassName("corners");
var len = corners.length;
while (len > 0) {
corners[0].classList.remove("corners");
--len;
}
}.header{
background: #4ABDAC;
color: #fff;
margin: 1px;
}
hr{
border-top: 3px double #2a3132;
}
ul{
list-style: none;
margin: 0;
padding: 0;
overflow: hidden;
background-color: #90afc5;
}
li{
float: left;
border: 2px solid #336b87;
padding: 3px;
margin: 3px;
}
li>a{
display: block;
color: #2a3132;
text-decoration: none;
padding: 10px 14px;
}
#color{
margin-left: 150px;
}
#rect{
margin-left: 100px;
}
li>a:hover{
color: #763626;
cursor: pointer;
}
#canvas{
background: #66a5ad;
position: relative;
height: 1200px;
width: 100%;
}
.corners{
position: absolute;
height: 10px;
width: 10px;
background:#fff;
border: 1px solid black;
display: none;
}
.selected .corners{
display: inline-block;
}
.cornerUpLeft{
top: -5px;
left: -5px;
}
.cornerUpRight{
top: -5px;
right: -5px;
}
.cornerBtmLeft{
bottom: -5px;
left: -5px;
}
.cornerBtmRight{
bottom: -5px;
right: -5px;
}
.rectangle{
position: absolute;
}
.colorBox{
border: 1px solid black;
height: 20px;
width: 20px;
list-style: none;
}