根据bootstrap的modal来显示loading动效。
核心内容：
1.图片转base64方法；
// 图片压缩-start function run(input_file,get_data){ /*input_file：文件按钮对象*/ /*get_data: 转换成功后执行的方法*/ if ( typeof(FileReader) === 'undefined' ){ alert("抱歉，你的浏览器不支持 FileReader，不能将图片转换为Base64，请使用现代浏览器操作！"); } else { try{ /*图片转Base64 核心代码*/ var file = input_file.files[0]; //这里我们判断下类型如果不是图片就返回 去掉就可以上传任意文件 if(!/image/w+/.test(file.type)){ alert("请确保文件为图像类型"); return false; } var reader = new FileReader(); reader.onload = function(){ get_data(this.result); }; reader.readAsDataURL(file); }catch (e){ } } } // 图片压缩-end
使用：
<input type="file" class="up-btn" id="u-btn1">
//上传照片 $("#u-btn1").change(function () { //转bese64 run(this, function (bs_img) { console.log(bs_img); }); });
2，modal垂直居中方法：
//modal垂直居中-start function centerModals() { $('#loadModal').each(function(i) { var $clone = $(this).clone().css('display','block').appendTo('body'); var top = Math.round(($clone.height() - $clone.find('.modal-content').height()) / 2); top = top > 0 ? top : 0; $clone.remove(); $(this).find('.modal-content').css("margin-top", top); }); } //modal垂直居中-end
使用方法：
$('#loadModal').on('show.bs.modal', centerModals);
$(function(){
//页面大小变化是仍然保证模态框水平垂直居中
$(window).on('resize', centerModals);
})
3，modal的lodaling结构：
<!-- modal-loading-start --> <div class="modal fade" id="loadModal"> <div class="modal-dialog"> <div class="modal-content"> <img class="center-block" alt="" src="data:image/gif;base64,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" /> </div> </div> </div> <!-- modal-loading-end -->
案例完整源码：
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <meta name="viewport" content="width=device-width, initial-scale=1.0"> <meta http-equiv="X-UA-Compatible" content="ie=edge"> <title>Document</title> <link rel="stylesheet" href="https://cdn.bootcss.com/bootstrap/3.3.7/css/bootstrap.css"> <style> .modal-content { background-color: transparent; box-shadow: none; border:none; } .file-box{ width:200px; } .u-img { width:100%; vertical-align: middle; } .up-btn { display:block; position: absolute; display: block; width:200px; /* 100%; */ height: 100%; opacity: 0; filter: alpha(opacity=0); } </style> </head> <body> <form action="" role="form" class="form-horizontal enter1form"> <div class="row enter-uploader"> <div class="col-sm-6"> <span><span style="color:red">*</span>照片：</span> <!-- <input type="hidden" id="btnid7" name="btnid7"> <input type="hidden" id="btnfile7" name="btnfile7"> --> <input type="file" class="up-btn" id="u-btn1"> <div class="file-box"> <img id="file-img7" class="u-img" src="enter01.png" alt=""> </div> </div> <div class="col-sm-6"> <img id="up-img" class="u-img"> </div> </div> </form> <h1>base64</h1> <textarea style="display: block; 100%;height: 30em;"></textarea> <!-- modal-loading-start --> <div class="modal fade" id="loadModal"> <div class="modal-dialog"> <div class="modal-content"> <img class="center-block" alt="" src="data:image/gif;base64,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" /> </div> </div> </div> <!-- modal-loading-end --> </body> </html> <script type="text/javascript" src="https://cdn.bootcss.com/jquery/3.2.1/jquery.js"></script> <script type="text/javascript" src="https://cdn.bootcss.com/bootstrap/3.3.7/js/bootstrap.js"></script> <script> // 图片压缩-start function run(input_file,get_data){ /*input_file：文件按钮对象*/ /*get_data: 转换成功后执行的方法*/ if ( typeof(FileReader) === 'undefined' ){ alert("抱歉，你的浏览器不支持 FileReader，不能将图片转换为Base64，请使用现代浏览器操作！"); } else { try{ /*图片转Base64 核心代码*/ var file = input_file.files[0]; //这里我们判断下类型如果不是图片就返回 去掉就可以上传任意文件 if(!/image/w+/.test(file.type)){ alert("请确保文件为图像类型"); return false; } var reader = new FileReader(); reader.onload = function(){ get_data(this.result); }; reader.readAsDataURL(file); }catch (e){ } } } // 图片压缩-end //modal垂直居中-start function centerModals() { $('#loadModal').each(function(i) { var $clone = $(this).clone().css('display','block').appendTo('body'); var top = Math.round(($clone.height() - $clone.find('.modal-content').height()) / 2); top = top > 0 ? top : 0; $clone.remove(); $(this).find('.modal-content').css("margin-top", top); }); } //modal垂直居中-end // 隐藏loading function hideModal(){ $('#loadModal').modal('hide'); } // 显示loading function showModal(){ $('#loadModal').on('show.bs.modal', centerModals); $('#loadModal').modal({backdrop:'static',keyboard:false,show:true}); } //modal垂直居中-end $(function(){ //页面大小变化是仍然保证模态框水平垂直居中 $(window).on('resize', centerModals); //上传照片 $("#u-btn1").change(function () { //转bese64 run(this, function (bs_img) { $('#up-img').attr('src',bs_img); $('textarea').val(bs_img); console.log(bs_img); showModal(); $.ajax({ type: "POST", data:{base64_img:bs_img}, url: "", dataType: "json", beforeSend: function(){ showModal(); }, success: function(data){ if (data){ hideModal(); }else{ hideModal(); } } }); }); }); }) </script>
预览地址：
https://besswang.github.io/bs-loading/index.html