Rumah > Soal Jawab > teks badan
Saya tertanya-tanya sama ada/bagaimana saya boleh menyimpan kedudukan yang saya alihkan div boleh seret ke atas meja, jadi apabila halaman dimuat semula ia akan kembali ke tempat ia berhenti (dari pangkalan data MySQL).
Saya telah membaca beberapa artikel berkaitan, tetapi semuanya tentang menggunakan jquery (acara, ui) dengan AJAX.
Ini kod saya:
var p = document.getElementsByTagName('p'); var choice = document.getElementsByClassName('choice'); var dragItem = null; for(var i of p){ i.addEventListener('dragstart', dragStart); i.addEventListener('dragend', dragEnd); } function dragStart(){ dragItem = this; setTimeout(()=>this.style.display = "none", 0); } function dragEnd(){ setTimeout(()=>this.style.display = "block", 0); dragItem = null; } for(j of choice){ j.addEventListener('dragover', dragOver); j.addEventListener('dragenter', dragEnter); j.addEventListener('dragleave', dragLeave); j.addEventListener('drop', Drop); } function Drop(){ this.append(dragItem); } function dragOver(e){ e.preventDefault(); this.style.border = "2px dotted cyan"; } function dragEnter(e){ e.preventDefault(); } function dragLeave(e){ this.style.border = "none"; }
section{ width: 1000px; height: 360px; margin: 100px auto; display: flex; justify-content: space-around; } h1{ text-align: center; } div{ width: 200px; height: 90%; padding: 20px; margin: 10px; background: #fafafa; box-sizing: border-box; } p{ font-weight: bold; border-radius: 5px; padding: 5px; color: white; background: red; } table, th, td { border:1px solid black; } button{ width: 100px; height: 15px; padding: 15px; margin: 10px; background: gray; box-sizing: border-box; }
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <meta name="viewport" content="width=device-width, initial-scale=1.0"> <title>test drag & drop </title> </head> <body> <h1> it's just a test for js </h1> <section> <div2> <table style="width:100%"> <tr> <th>time</th> <th>DIM</th> <th>LUN</th> </tr> <tr> <td>8:00 - 9:00</td> <td><div class="choice"></div> S1-1</td> <td><div class="choice"></div>S1-2</td> </tr> <tr> <td>9:00 - 10:00</td> <td><div class="choice"></div>S2-1</td> <td><div class="choice"></div>S2-2</td> </tr> </table> <button>save</button> </div2> <div class="choice"> <p draggable="true">MODULE 1</p> <p draggable="true">MODULE 2</p> <p draggable="true">MODULE 3</p> <p draggable="true">MODULE 4</p> <p draggable="true">MODULE 5</p> </div> </section> </body> </html>
P粉7294365372024-02-04 16:28:41
Ini mungkin jawapan yang terlalu rumit. Tetapi saya rasa cara terbaik ialah menyimpan module
对象的数组。每个 module
都有一个 position
属性,每次移动模块时都需要更新该属性。您还可以使用 data
atribut html dalam JavaScript untuk menyimpan kedudukan elemen itu sendiri pada elemen (https://developer.mozilla.org/en-US/docs/Learn/HTML/Howto/Use_data_attributes ). Ini kod saya:
Javascript:
var dragItem = null;
let modules = loadDataFromServer();
//Initial UI
updateUI(modules);
function dragStart() {
console.log("Start")
dragItem = this;
setTimeout(() => this.style.display = "none", 0);
}
function dragEnd() {
console.log("End")
setTimeout(() => this.style.display = "block", 0);
dragItem = null;
}
function Drop() {
console.log("Drop")
console.log(dragItem)
this.append(dragItem);
moveModuleTo(modules.length - 1, modules[dragItem.dataset.position])
}
function dragOver(e) {
e.preventDefault();
this.style.border = "2px dotted cyan";
}
function dragEnter(e) {
e.preventDefault();
}
function dragLeave(e) {
this.style.border = "none";
}
//Added Code
function loadDataFromServer() {
//return an array of modules
return [
{
title: "Module 1",
position: 0
},
{
title: "Module 2",
position: 1
},
{
title: "Module 3",
position: 2
},
{
title: "Module 4",
position: 3
},
{
title: "Module 5",
position: 4
},
]
}
function moveModuleTo(position, module) {
if (module.position < position) {
//Module is moving down the list
console.log(position)
console.log(module.position)
for (let i = module.position; i < position; i++) {
modules[i] = modules[i + 1];
modules[i].position = i
}
} else {
//Module is moving up the list
for (let i = module.position - 1; i > position; i--) {
modules[i] = modules[i - 1]
modules[i].position = i + 1;
}
}
modules[position] = module
modules[position].position = position
console.log(modules)
//Update UI and database
updateUI(modules)
}
function updateUI(modules) {
let choice = document.getElementsByClassName('choice');
//Remove old Modules
const draggableContainer = document.getElementById("draggableContainer")
while (draggableContainer.firstChild) {
draggableContainer.removeChild(draggableContainer.lastChild)
}
//Add updated Modules
modules.forEach(item => {
console.log("yeet")
let newDraggableItem = document.createElement('p')
newDraggableItem.innerHTML = `${item.title}`
newDraggableItem.draggable = true
newDraggableItem.dataset.position = item.position
draggableContainer.appendChild(newDraggableItem);
});
//ReAdd Event listeners
var p = document.getElementsByTagName('p');
for (var i of p) {
i.addEventListener('dragstart', dragStart);
i.addEventListener('dragend', dragEnd);
}
for (j of choice) {
j.addEventListener('dragover', dragOver);
j.addEventListener('dragenter', dragEnter);
j.addEventListener('dragleave', dragLeave);
j.addEventListener('drop', Drop);
}
}
HTML:
test drag & drop it's just a test for js
sssccc
time DIM LUN 8:00 - 9:00 S1-1 S1-2 9:00 - 10:00 S2-1 S2-2
Untuk mengemas kini pangkalan data, anda boleh mengisih tatasusunan mengikut nilai write
数据库调用。然后每次加载页面时,只需根据 position
setiap kali anda mengalihkan modul. Harap ini membantu!