如何在上传前后预览图片？

我将在表单中预览图像或照片，但它不起作用，HTML代码如下所示：

 
Upload Image: 
 
Save
 
  
  

并在下面合并了JS代码/脚本：

  $(document).ready(function(){ var thumb=$('#thumb'); new AjaxUpload('imageUpload',{ action:$('newHotnessForm').attr('action'), name:'image', onSubmit:function(file,extension){ $('#preview').addClass('loading'); }, onComplete:function(file,response){ thumb.load(function(){ $('#preview').removeClass('loading'); thumb.unbind(); }); thumb.attr('src',response); } }); }); 

我的表格上有两个主要问题：
1.为什么图像或图片的预览不起作用？
2.单击保存按钮时如何粘贴表单中的照片，它将链接到我创建的另一个php或php页面？

Answer 1

试试这个:(预览）

在这里工作演示>

Answer 2

meVeekay的答案很好，我只是通过做两件事来使它更加即兴。

1. 检查浏览器是否支持HTML5 FileReader（）。

2. 通过检查其扩展名仅允许上传图像文件。

HTML：

jQuery：

 $("https://stackoverflow.com/questions/16207575/how-to-preview-a-image-before-and-after-upload/#fileUpload").on('change', function () { var imgPath = $(this)[0].value; var extn = imgPath.substring(imgPath.lastIndexOf('.') + 1).toLowerCase(); if (extn == "gif" || extn == "png" || extn == "jpg" || extn == "jpeg") { if (typeof (FileReader) != "undefined") { var image_holder = $("https://stackoverflow.com/questions/16207575/how-to-preview-a-image-before-and-after-upload/#image-holder"); image_holder.empty(); var reader = new FileReader(); reader.onload = function (e) { $("", { "src": e.target.result, "class": "thumb-image" }).appendTo(image_holder); } image_holder.show(); reader.readAsDataURL($(this)[0].files[0]); } else { alert("This browser does not support FileReader."); } } else { alert("Pls select only images"); } }); 

有关FileReader（）的详细了解

查看此文章：在上传之前使用FileReader（）预览图像。

Answer 3

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