javascript - 单击提交按钮之前表单不断重定向

Question

我构建了这个函数，当用户单击按钮时执行；它将一个列表和 2 个按钮元素插入到封装在表单中的有序列表中。然而，每当我单击生成按钮时，它都会立即生成新元素，然后立即重定向到表单的操作/处理 php 页面，由于字段未填充等原因，该页面会重定向回上一页。我没有按下提交，所以我很困惑为什么它要处理表单？

这是我的 JS 函数:

function spawnSilly() //spawn chapters function
        {

            var div = document.createElement("LI"); //creating elements
            var input = document.createElement("INPUT");
            var button = document.createElement("BUTTON");
            var del_button = document.createElement("BUTTON")
            input.setAttribute("type", "text");     //setting attributes
            input.setAttribute("name", "chapterInput" + stringNumber);
            input.setAttribute("placeholder", "Title");
            input.setAttribute("id", "var timestamp = new Date().getUTCMilliseconds();")
            button.setAttribute("type", "button");
            button.setAttribute("onClick", "redirect()");
            button.setAttribute("id", "var timestamp = new Date().getUTCMilliseconds();")
            button.innerHTML = "Edit";
            div.setAttribute("id", "var timestamp = new Date().getUTCMilliseconds();")
            del_button.setAttribute("id", "var timestamp = new Date().getUTCMilliseconds();")
            del_button.innerHTML = "Delete Chapter";
            del_button.setAttribute("onClick", "removeElement(this.id)")
            div.appendChild(input)      //appending to list
            div.appendChild(button)
            div.appendChild(del_button);
            var chapterNumber = getCount(document.getElementById('spawnList'), false) //setting number of chapter
            var number = $('#spawnList').children(); //fetching number of children in list
            var stringNumber = String(number) //setting chapter number to string for name attribute in input
            var list = document.getElementById("spawnList");
            list.insertBefore(div, list.childNodes[number]); //inserting one after another
            var newChapterNumber = chapterNumber + 1;  //setting elements class as their chapter number
            input.setAttribute("class", newChapterNumber);
            button.setAttribute("class", newChapterNumber);
            div.setAttribute("class", newChapterNumber);
            del_button.setAttribute("class", newChapterNumber);
            input.setAttribute("index", newChapterNumber);
            button.setAttribute("index", newChapterNumber);
            div.setAttribute("index", newChapterNumber);
            del_button.setAttribute("index", newChapterNumber);
        }

<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<form action="title-processing.php" method="post">
    <ol id="spawnList">


    </ol>
    <button id="spawnbtn" onClick="spawnSilly();">Add Chapter</button>
    <button type="submit" name="Submit">Save</button>
</form>

任何帮助都会非常好! :)

Answer 1

按钮的默认 type= 为 submit - 因此，通过省略 type=，系统会添加 type=submit，所以你的按钮:

<button id="spawnbtn" onClick="spawnSilly();">Add Chapter</button>

实际上是

<button type='submit' id="spawnbtn" onClick="spawnSilly();">Add Chapter</button>

明确指定类型以停止提交表单:

<button type='button' id="spawnbtn" onClick="spawnSilly();">Add Chapter</button>