即使表中没有选择，也会弹出警报 [英] Alert popping up even if no selection is made in the table
本文介绍了即使表中没有选择，也会弹出警报的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！
问题描述
我有一个引导程序模式，其中包含一个用户表。我可以从表中选择一个用户，然后单击保存，将显示所选用户的详细信息，并且我会收到一条警告，指出数据已成功保存！。
I've a bootstrap modal which contains a table of users. I can select a user from the table and on clicking 'save', the details of selected user is displayed and I get an alert stating 'Data saved successfully!'.
警报位于代码中'saveData（）'方法的末尾。
The alert is at the end of the 'saveData()' method in my code.
但是，即使没有从表中选择任何行，当我单击保存时，我仍然收到相同的警报数据成功保存！。
However, even when no row is selected from the table, when I click on save, I still get the same alert 'Data saved successfully!'.
我如何确保仅在添加了选定使用项的详细信息后才显示警报？
How do I ensure, that the alert only shows up if the details of a selected used is added?
var currentPageNo = 0; // Keep track of currently displayed page
// Select button that is descendant of userList
$('#userList .prev-btn').click(function(){
userList(currentPageNo-10);
});
$('#userList .next-btn').click(function(){
userList(currentPageNo+10);
});
$('#adminList .prev-btn').click(function(){
adminList(currentPageNo-10);
});
$('#adminList .next-btn').click(function(){
adminList(currentPageNo+10);
});
function userList(pageNo) {
var resType="userList";
createTable(resType,pageNo);
}
function adminList(pageNo) {
var resType="adminList";
createTable(resType,pageNo);
}
function createTable(resType, pageNo) {
// Update global variable
currentPageNo = pageNo;
// Set visibility of the correct "prev" button:
$('#' + resType + ' .prev-btn').toggle(pageNo > 0);
// Ask one record more than needed, to determine if there are more records after this page:
$.getJSON("https://api.randomuser.me/?results=11&resType="+resType + "&pageIndex=" + pageNo, function(data) {
var $table = $('#' + resType + ' table');
$('tr:has(td)', $table).empty();
// Check if there's an extra record which we do not display,
// but determines that there is a next page
$('#' + resType + ' .next-btn').toggle(data.results.length > 10);
// Slice results, so 11th record is not included:
data.results.slice(0, 10).forEach(function (record, i) { // add second argument for numbering records
var json = JSON.stringify(record);
$table.append(
$('<tr>').append(
$('<td>').append(
$('<input>').attr('type', 'checkbox')
.addClass('selectRow')
.val(json),
(i+1+pageNo) // display row number
),
$('<td>').append(
$('<a>').attr('href', record.picture.thumbnail)
.addClass('imgurl')
.attr('target', '_blank')
.text(record.name.first)
),
$('<td>').append(record.dob)
)
);
});
// Show the prev and/or buttons
}).fail(function(error) {
console.log("**********AJAX ERROR: " + error);
});
}
var savedData = []; // The objects as array, so to have an order.
function saveData(){
var errors = [];
// Add selected to map
$('input.selectRow:checked').each(function(count) {
// Get the JSON that is stored as value for the checkbox
var obj = JSON.parse($(this).val());
// See if this URL was already collected (that's easy with Set)
if (savedData.find(record => record.picture.thumbnail === obj.picture.thumbnail)) {
errors.push(obj.name.first);
} else {
// Append it
savedData.push(obj);
}
});
refreshDisplay();
if (errors.length) {
alert('The following were already selected:\n' + errors.join('\n'));
} else {
alert('Data saved successfully!');
}
}
function refreshDisplay() {
$('.container').html('');
savedData.forEach(function (obj) {
// Reset container, and append collected data (use jQuery for appending)
$('.container').append(
$('<div>').addClass('parent').append(
$('<label>').addClass('dataLabel').text('Name: '),
obj.name.first + ' ' + obj.name.last,
$('<br>'), // line-break between name & pic
$('<img>').addClass('myLink').attr('src', obj.picture.thumbnail), $('<br>'),
$('<label>').addClass('dataLabel').text('Date of birth: '),
obj.dob, $('<br>'),
$('<label>').addClass('dataLabel').text('Address: '), $('<br>'),
obj.location.street, $('<br>'),
obj.location.city + ' ' + obj.location.postcode, $('<br>'),
obj.location.state, $('<br>'),
$('<button>').addClass('removeMe').text('Delete'),
$('<button>').addClass('top-btn').text('Swap with top'),
$('<button>').addClass('down-btn').text('Swap with down')
)
);
})
// Clear checkboxes:
$('.selectRow').prop('checked', false);
handleEvents();
}
function logSavedData(){
// Convert to JSON and log to console. You would instead post it
// to some URL, or save it to localStorage.
console.log(JSON.stringify(savedData, null, 2));
}
function getIndex(elem) {
return $(elem).parent('.parent').index();
}
$(document).on('click', '.removeMe', function() {
// Delete this from the saved Data
savedData.splice(getIndex(this), 1);
// And redisplay
refreshDisplay();
});
/* Swapping the displayed articles in the result list */
$(document).on('click', ".down-btn", function() {
var index = getIndex(this);
// Swap in memory
savedData.splice(index, 2, savedData[index+1], savedData[index]);
// And redisplay
refreshDisplay();
});
$(document).on('click', ".top-btn", function() {
var index = getIndex(this);
// Swap in memory
savedData.splice(index-1, 2, savedData[index], savedData[index-1]);
// And redisplay
refreshDisplay();
});
/* Disable top & down buttons for the first and the last article respectively in the result list */
function handleEvents() {
$(".top-btn, .down-btn").prop("disabled", false).show();
$(".parent:first").find(".top-btn").prop("disabled", true).hide();
$(".parent:last").find(".down-btn").prop("disabled", true).hide();
}
$(document).ready(function(){
$('#showExtForm-btn').click(function(){
$('#extUser').toggle();
});
$("#extUserForm").submit(function(e){
addExtUser();
return false;
});
});
function addExtUser() {
var extObj = {
name: {
title: "mr", // No ladies? :-)
first: $("#name").val(),
// Last name ?
},
dob: $("#dob").val(),
picture: {
thumbnail: $("#myImg").val()
},
location: { // maybe also ask for this info?
}
};
savedData.push(extObj);
refreshDisplay(); // Will show some undefined stuff (location...)
}
.parent {
background-color: #0000FF;
color: white;
border: 1px solid black;
}
<link href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css" rel="stylesheet"/>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/js/bootstrap.min.js"></script>
<button class="btn btn-primary btn-sm" data-toggle="modal" data-target="#userList" onclick="userList(0)">User List</button>
<button class="btn btn-primary btn-sm" onclick="logSavedData()">Get Saved Data</button>
<button class="btn btn-primary btn-sm" data-toggle="modal" data-target="#adminList" onclick="adminList(0)">User Admin</button>
<button class="btn btn-primary btn-sm" data-toggle="modal" data-target="#extUser">Open External Form</button>
<div class="modal fade" id="userList" role="dialog">
<div class="modal-dialog modal-lg">
<div class="modal-content">
<div class="modal-header">
<button type="button" class="close" data-dismiss="modal">×</button>
<h4 class="modal-title">User List</h4>
</div>
<div class="modal-body">
<div class="table-responsive">
<table class="table table-bordered table-hover" id="datatable">
<tr>
<th>Select</th>
<th>Name</th>
<th>DOB</th>
</tr>
</table>
</div>
<div class="row">
<div class="col-sm-offset-3 col-sm-4">
<button type="button" class="btn btn-primary prev-btn"><span class="glyphicon glyphicon-chevron-left"></span></button>
</div>
<div class="col-sm-4">
<button type="button" class="btn btn-primary next-btn"><span class="glyphicon glyphicon-chevron-right"></span></button>
</div>
</div>
<hr/>
<div class="row">
<div class="col-sm-offset-3 col-sm-4">
<button type="button" class="btn btn-primary btn-sm" onclick="saveData()">Save selected</button>
</div>
<div class="col-sm-4">
<button type="button" class="btn btn-primary btn-sm close-less-modal" data-dismiss="modal">Close</button>
</div>
</div>
<br />
</div>
</div>
</div>
</div>
<div class="modal fade" id="adminList" role="dialog">
<div class="modal-dialog modal-lg">
<div class="modal-content">
<div class="modal-header">
<button type="button" class="close" data-dismiss="modal">×</button>
<h4 class="modal-title">Admin List</h4>
</div>
<div class="modal-body">
<div class="table-responsive">
<table class="table table-bordered table-hover" id="datatable">
<tr>
<th>Select</th>
<th>Name</th>
<th>DOB</th>
</tr>
</table>
</div>
<div class="row">
<div class="col-sm-offset-3 col-sm-4">
<button type="button" class="btn btn-primary prev-btn"><span class="glyphicon glyphicon-chevron-left"></span></button>
</div>
<div class="col-sm-4">
<button type="button" class="btn btn-primary next-btn"><span class="glyphicon glyphicon-chevron-right"></span></button>
</div>
</div>
<hr/>
<div class="row">
<div class="col-sm-offset-3 col-sm-4">
<button type="button" class="btn btn-primary btn-sm" onclick="saveData()">Save selected</button>
</div>
<div class="col-sm-4">
<button type="button" class="btn btn-primary btn-sm close-less-modal" data-dismiss="modal">Close</button>
</div>
</div>
<br />
</div>
</div>
</div>
</div>
<div class="modal fade" id="extUser" role="dialog">
<div class="modal-dialog modal-lg">
<!-- External User-->
<div class="modal-content">
<div class="modal-header">
<button type="button" class="close" data-dismiss="modal">×</button>
<h4 class="modal-title">Add External User</h4>
</div>
<div class="modal-body">
<form class="form-horizontal" id="extUserForm">
<div class="form-group">
<label class="control-label col-sm-3" for="name">Name:</label>
<div class="col-sm-8">
<input type="text" class="form-control" id="name" name="name" required>
</div>
</div>
<div class="form-group">
<label class="control-label col-sm-3" for="myImg">Image:</label>
<div class="col-sm-8">
<input type="text" class="form-control" id="myImg" name="myImg" required>
</div>
</div>
<div class="form-group">
<label class="control-label col-sm-3" for="dob">DOB:</label>
<div class="col-sm-8">
<input type="date" class="form-control" id="dob" name="dob" required>
</div>
</div>
<hr />
<div class="form-group">
<div class="col-sm-offset-3 col-sm-3">
<button class="btn btn-primary btn-sm">Submit</button>
</div>
<div class="col-sm-3">
<button type="reset" class="btn btn-primary btn-sm">Reset</button>
</div>
<div class="col-sm-3">
<button type="button" class="btn btn-primary btn-sm close-external-modal" data-dismiss="modal">Close</button>
</div>
</div>
</form>
</div>
</div>
</div>
</div>
<div class="container"></div>
注意：每个复选框都包含选择时存储在 savedData数组中的对象。
Note: Each of the checkboxes contain the object which on selection get stored in the 'savedData' array.
这是完整的代码
推荐答案
当您遍历选中的复选框（选择用户）时，您可以递增变量以检查选中的用户数量，如果选择了至少一个用户则发出警报消息如下：
When you loop through checkboxes checked (select users) you can increment variable to check how many users selected and if atleast one is selected then alert message as follows:
var currentPageNo = 0; // Keep track of currently displayed page
// Select button that is descendant of userList
$('#userList .prev-btn').click(function(){
userList(currentPageNo-10);
});
$('#userList .next-btn').click(function(){
userList(currentPageNo+10);
});
$('#adminList .prev-btn').click(function(){
adminList(currentPageNo-10);
});
$('#adminList .next-btn').click(function(){
adminList(currentPageNo+10);
});
function userList(pageNo) {
var resType="userList";
createTable(resType,pageNo);
}
function adminList(pageNo) {
var resType="adminList";
createTable(resType,pageNo);
}
function createTable(resType, pageNo) {
// Update global variable
currentPageNo = pageNo;
// Set visibility of the correct "prev" button:
$('#' + resType + ' .prev-btn').toggle(pageNo > 0);
// Ask one record more than needed, to determine if there are more records after this page:
$.getJSON("https://api.randomuser.me/?results=11&resType="+resType + "&pageIndex=" + pageNo, function(data) {
var $table = $('#' + resType + ' table');
$('tr:has(td)', $table).empty();
// Check if there's an extra record which we do not display,
// but determines that there is a next page
$('#' + resType + ' .next-btn').toggle(data.results.length > 10);
// Slice results, so 11th record is not included:
data.results.slice(0, 10).forEach(function (record, i) { // add second argument for numbering records
var json = JSON.stringify(record);
$table.append(
$('<tr>').append(
$('<td>').append(
$('<input>').attr('type', 'checkbox')
.addClass('selectRow')
.val(json),
(i+1+pageNo) // display row number
),
$('<td>').append(
$('<a>').attr('href', record.picture.thumbnail)
.addClass('imgurl')
.attr('target', '_blank')
.text(record.name.first)
),
$('<td>').append(record.dob)
)
);
});
// Show the prev and/or buttons
}).fail(function(error) {
console.log("**********AJAX ERROR: " + error);
});
}
var savedData = []; // The objects as array, so to have an order.
function saveData(){
var errors = [];
// Add selected to map
var selectedUsersCount = 0;
$('input.selectRow:checked').each(function(count) {
selectedUsersCount = selectedUsersCount + 1;
// Get the JSON that is stored as value for the checkbox
var obj = JSON.parse($(this).val());
// See if this URL was already collected (that's easy with Set)
if (savedData.find(record => record.picture.thumbnail === obj.picture.thumbnail)) {
errors.push(obj.name.first);
} else {
// Append it
savedData.push(obj);
}
});
refreshDisplay();
if (errors.length) {
alert('The following were already selected:\n' + errors.join('\n'));
} else if(selectedUsersCount > 0){
alert('Data saved successfully!');
}
}
function refreshDisplay() {
$('.container').html('');
savedData.forEach(function (obj) {
// Reset container, and append collected data (use jQuery for appending)
$('.container').append(
$('<div>').addClass('parent').append(
$('<label>').addClass('dataLabel').text('Name: '),
obj.name.first + ' ' + obj.name.last,
$('<br>'), // line-break between name & pic
$('<img>').addClass('myLink').attr('src', obj.picture.thumbnail), $('<br>'),
$('<label>').addClass('dataLabel').text('Date of birth: '),
obj.dob, $('<br>'),
$('<label>').addClass('dataLabel').text('Address: '), $('<br>'),
obj.location.street, $('<br>'),
obj.location.city + ' ' + obj.location.postcode, $('<br>'),
obj.location.state, $('<br>'),
$('<button>').addClass('removeMe').text('Delete'),
$('<button>').addClass('top-btn').text('Swap with top'),
$('<button>').addClass('down-btn').text('Swap with down')
)
);
})
// Clear checkboxes:
$('.selectRow').prop('checked', false);
handleEvents();
}
function logSavedData(){
// Convert to JSON and log to console. You would instead post it
// to some URL, or save it to localStorage.
console.log(JSON.stringify(savedData, null, 2));
}
function getIndex(elem) {
return $(elem).parent('.parent').index();
}
$(document).on('click', '.removeMe', function() {
// Delete this from the saved Data
savedData.splice(getIndex(this), 1);
// And redisplay
refreshDisplay();
});
/* Swapping the displayed articles in the result list */
$(document).on('click', ".down-btn", function() {
var index = getIndex(this);
// Swap in memory
savedData.splice(index, 2, savedData[index+1], savedData[index]);
// And redisplay
refreshDisplay();
});
$(document).on('click', ".top-btn", function() {
var index = getIndex(this);
// Swap in memory
savedData.splice(index-1, 2, savedData[index], savedData[index-1]);
// And redisplay
refreshDisplay();
});
/* Disable top & down buttons for the first and the last article respectively in the result list */
function handleEvents() {
$(".top-btn, .down-btn").prop("disabled", false).show();
$(".parent:first").find(".top-btn").prop("disabled", true).hide();
$(".parent:last").find(".down-btn").prop("disabled", true).hide();
}
$(document).ready(function(){
$('#showExtForm-btn').click(function(){
$('#extUser').toggle();
});
$("#extUserForm").submit(function(e){
addExtUser();
return false;
});
});
function addExtUser() {
var extObj = {
name: {
title: "mr", // No ladies? :-)
first: $("#name").val(),
// Last name ?
},
dob: $("#dob").val(),
picture: {
thumbnail: $("#myImg").val()
},
location: { // maybe also ask for this info?
}
};
savedData.push(extObj);
refreshDisplay(); // Will show some undefined stuff (location...)
}
.parent {
background-color: #0000FF;
color: white;
border: 1px solid black;
}
<link href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css" rel="stylesheet"/>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/js/bootstrap.min.js"></script>
<button class="btn btn-primary btn-sm" data-toggle="modal" data-target="#userList" onclick="userList(0)">User List</button>
<button class="btn btn-primary btn-sm" onclick="logSavedData()">Get Saved Data</button>
<button class="btn btn-primary btn-sm" data-toggle="modal" data-target="#adminList" onclick="adminList(0)">User Admin</button>
<button class="btn btn-primary btn-sm" data-toggle="modal" data-target="#extUser">Open External Form</button>
<div class="modal fade" id="userList" role="dialog">
<div class="modal-dialog modal-lg">
<div class="modal-content">
<div class="modal-header">
<button type="button" class="close" data-dismiss="modal">×</button>
<h4 class="modal-title">User List</h4>
</div>
<div class="modal-body">
<div class="table-responsive">
<table class="table table-bordered table-hover" id="datatable">
<tr>
<th>Select</th>
<th>Name</th>
<th>DOB</th>
</tr>
</table>
</div>
<div class="row">
<div class="col-sm-offset-3 col-sm-4">
<button type="button" class="btn btn-primary prev-btn"><span class="glyphicon glyphicon-chevron-left"></span></button>
</div>
<div class="col-sm-4">
<button type="button" class="btn btn-primary next-btn"><span class="glyphicon glyphicon-chevron-right"></span></button>
</div>
</div>
<hr/>
<div class="row">
<div class="col-sm-offset-3 col-sm-4">
<button type="button" class="btn btn-primary btn-sm" onclick="saveData()">Save selected</button>
</div>
<div class="col-sm-4">
<button type="button" class="btn btn-primary btn-sm close-less-modal" data-dismiss="modal">Close</button>
</div>
</div>
<br />
</div>
</div>
</div>
</div>
<div class="modal fade" id="adminList" role="dialog">
<div class="modal-dialog modal-lg">
<div class="modal-content">
<div class="modal-header">
<button type="button" class="close" data-dismiss="modal">×</button>
<h4 class="modal-title">Admin List</h4>
</div>
<div class="modal-body">
<div class="table-responsive">
<table class="table table-bordered table-hover" id="datatable">
<tr>
<th>Select</th>
<th>Name</th>
<th>DOB</th>
</tr>
</table>
</div>
<div class="row">
<div class="col-sm-offset-3 col-sm-4">
<button type="button" class="btn btn-primary prev-btn"><span class="glyphicon glyphicon-chevron-left"></span></button>
</div>
<div class="col-sm-4">
<button type="button" class="btn btn-primary next-btn"><span class="glyphicon glyphicon-chevron-right"></span></button>
</div>
</div>
<hr/>
<div class="row">
<div class="col-sm-offset-3 col-sm-4">
<button type="button" class="btn btn-primary btn-sm" onclick="saveData()">Save selected</button>
</div>
<div class="col-sm-4">
<button type="button" class="btn btn-primary btn-sm close-less-modal" data-dismiss="modal">Close</button>
</div>
</div>
<br />
</div>
</div>
</div>
</div>
<div class="modal fade" id="extUser" role="dialog">
<div class="modal-dialog modal-lg">
<!-- External User-->
<div class="modal-content">
<div class="modal-header">
<button type="button" class="close" data-dismiss="modal">×</button>
<h4 class="modal-title">Add External User</h4>
</div>
<div class="modal-body">
<form class="form-horizontal" id="extUserForm">
<div class="form-group">
<label class="control-label col-sm-3" for="name">Name:</label>
<div class="col-sm-8">
<input type="text" class="form-control" id="name" name="name" required>
</div>
</div>
<div class="form-group">
<label class="control-label col-sm-3" for="myImg">Image:</label>
<div class="col-sm-8">
<input type="text" class="form-control" id="myImg" name="myImg" required>
</div>
</div>
<div class="form-group">
<label class="control-label col-sm-3" for="dob">DOB:</label>
<div class="col-sm-8">
<input type="date" class="form-control" id="dob" name="dob" required>
</div>
</div>
<hr />
<div class="form-group">
<div class="col-sm-offset-3 col-sm-3">
<button class="btn btn-primary btn-sm">Submit</button>
</div>
<div class="col-sm-3">
<button type="reset" class="btn btn-primary btn-sm">Reset</button>
</div>
<div class="col-sm-3">
<button type="button" class="btn btn-primary btn-sm close-external-modal" data-dismiss="modal">Close</button>
</div>
</div>
</form>
</div>
</div>
</div>
</div>
<div class="container"></div>
这篇关于即使表中没有选择，也会弹出警报的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
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