我要做一个按钮，采取行动并将数据保存到数据库中。
一旦用户单击按钮，我希望JavaScript警报提供“是”和“取消”选项。如果用户选择“是”，数据将被插入数据库，否则将不采取任何操作。
如何显示这样的对话框？
当前回答
您可以使用JavaScript拦截onSubmit事件。
然后调用确认警报，然后获取结果。
其他回答
一个普通的JavaScript选项，带有一个用于创建自定义模式对话框的类，该对话框包含一个文本框：
jsfiddle：
https://jsfiddle.net/craigdude/uh82mjtb/2/
html格式：
<!DOCTYPE html>
<html>
<style>
.modal_dialog
{
box-sizing: border-box;
background-color: #ededed;
border-radius: 5px;
border: 0.5px solid #ccc;
font-family: sans-serif;
left: 30%;
margin-left: -50px;
padding: 15px 10px 10px 5px;
position: fixed;
text-align: center;
width: 320px;
}
</style>
<script src="./CustomModalDialog.js"></script>
<script>
var gCustomModalDialog = null;
/** this could be static html from the page in an "invisible" state */
function generateDynamicCustomDialogHtml(){
var html = "";
html += '<div id="custom_modal_dialog" class="modal_dialog">';
html += 'Name: <input id="name" placeholder="Name"></input><br><br>';
html += '<button id="okay_button">OK</button>';
html += '<button id="cancel_button">Cancel</button>';
html += '</div>';
return html;
}
function onModalDialogOkayPressed(event) {
var name = document.getElementById("name");
alert("Name entered: "+name.value);
}
function onModalDialogCancelPressed(event) {
gCustomModalDialog.hide();
}
function setupCustomModalDialog() {
var html = generateDynamicCustomDialogHtml();
gCustomModalDialog = new CustomModalDialog(html, "okay_button", "cancel_button",
"modal_position", onModalDialogOkayPressed, onModalDialogCancelPressed);
}
function showCustomModalDialog() {
if (! gCustomModalDialog) {
setupCustomModalDialog();
}
gCustomModalDialog.show();
gCustomModalDialog.setFocus("name");
}
</script>
<body>
<button onclick="showCustomModalDialog(this)">Show Dialog</button><br>
Some content
<div id="modal_position">
</div>
Some additional content
</body>
</html>
自定义模式对话框.js：
/** Encapsulates a custom modal dialog in pure JS
*/
class CustomModalDialog {
/**
* Constructs the modal content
* @param htmlContent - content of the HTML dialog to show
* @param okayControlElementId - elementId of the okay button, image or control
* @param cancelControlElementId - elementId of the cancel button, image or control
* @param insertionElementId - elementId of the <div> or whatever tag to
* insert the html at within the document
* @param callbackOnOkay - method to invoke when the okay button or control is clicked.
* @param callbackOnCancel - method to invoke when the cancel button or control is clicked.
* @param callbackTag (optional) - to allow object to be passed to the callbackOnOkay
* or callbackOnCancel methods when they're invoked.
*/
constructor(htmlContent, okayControlElementId, cancelControlElementId, insertionElementId,
callbackOnOkay, callbackOnCancel, callbackTag) {
this.htmlContent = htmlContent;
this.okayControlElementId = okayControlElementId;
this.cancelControlElementId = cancelControlElementId;
this.insertionElementId = insertionElementId;
this.callbackOnOkay = callbackOnOkay;
this.callbackOnCancel = callbackOnCancel;
this.callbackTag = callbackTag;
}
/** shows the custom modal dialog */
show() {
// must insert the HTML into the page before searching for ok/cancel buttons
var insertPoint = document.getElementById(this.insertionElementId);
insertPoint.innerHTML = this.htmlContent;
var okayControl = document.getElementById(this.okayControlElementId);
var cancelControl = document.getElementById(this.cancelControlElementId);
okayControl.addEventListener('click', event => {
this.callbackOnOkay(event, insertPoint, this.callbackTag);
});
cancelControl.addEventListener('click', event => {
this.callbackOnCancel(event, insertPoint, this.callbackTag);
});
} // end: method
/** hide the custom modal dialog */
hide() {
var insertPoint = document.getElementById(this.insertionElementId);
var okayControl = document.getElementById(this.okayControlElementId);
var cancelControl = document.getElementById(this.cancelControlElementId);
insertPoint.innerHTML = "";
okayControl.removeEventListener('click',
this.callbackOnOkay,
false
);
cancelControl.removeEventListener('click',
this.callbackOnCancel,
false
);
} // end: method
/** sets the focus to given element id
*/
setFocus(elementId) {
var focusElement = document.getElementById(elementId);
focusElement.focus();
if (typeof focusElementstr === "HTMLInputElement")
focusElement.select();
}
} // end: class
您可以使用JavaScript拦截onSubmit事件。
然后调用确认警报，然后获取结果。
我目前正在开发一个web工作流，它已经有了自己的通知/对话框，我最近（比如今天）创建了一个小型的自定义（并根据项目需要定制）是/否对话框。
所有对话框都显示在模态图层上。需要用户充分注意。
我以这种方式定义选项配置。此选项用于定义按钮文本，以及单击时与每个按钮关联的值：
optionsConfig = [
{ text: 'Yes', value: true },
{ text: 'No', value: false }
]
函数的用法如下：
const answer = await notifier.showDialog('choose an option', options.config);
if (answer) {
// 'Yes' was clicked
} else {
// 'No' was clicked!
}
我所做的只是为每个选项创建一个异步事件处理程序，这意味着每个按钮都有一个简单的处理程序。每个处理程序都返回选项的值。处理程序被推入数组中。然后将数组传递给Promise.rece，这是showDialog方法的返回值，它将对应于值的实际值（由处理程序返回的值）。
无法提供太多代码。正如我所说，这是一个非常具体的案例，但这个想法可能对其他实现有用。大约二十行代码。
另一种方法是：
$("input[name='savedata']").click(function(e){
var r = confirm("Are you sure you want to save now?");
//cancel clicked : stop button default action
if (r === false) {
return false;
}
//action continues, saves in database, no need for more code
});
var answer = window.confirm("Save data?");
if (answer) {
//some code
}
else {
//some code
}
使用window.conf而不是alert。这是实现该功能的最简单方法。
