Detailed explanation of image upload preview and deletion steps with JQuery

This time I will bring you a detailed explanation of the steps for uploading, previewing and deleting images with JQuery. What are the precautions for uploading and deleting images with JQuery? The following is a practical case, let’s take a look.

1. preview.2.0.html

nbsp;html>


 <title>上传图片预览</title>
 <meta>
 <link>
 <script></script>
 <script></script>
<script>
 $(function(){
  var p = new ImgPreview();
  p.preview({previewid:"imgupload1"}); 
  p.preview({previewid:"imgupload2"}); 
 });
</script>


 <p></p>
 <p></p>

2. srdz.preview.2.0.css

.btn-pic {
 display: block;
 position: relative;
 width: 120px;
 height: 40px;
 overflow: hidden;
 cursor: pointer;
 text-align: center;
}
 
.btn-pic-bg {
 border: 1px solid #ff9000;
 background: none repeat scroll 0 0 #ff9000;
 color: #ffffff;
 text-decoration: none;
}
 
.btn-pic span {
 display: block;
 line-height: 39px;
}
 
.ipt-bg {
 display: block;
 position: absolute;
 top: 0;
 left: 0;
 width: 120px;
 height: 40px;
 font-size: 100px;
 opacity: 0;
 filter: alpha(opacity=0);
}
 
.spanc{
 color: red;
}
 
.drt {
 float: right;
 display: none;
}
 
.dft {
 float: left;
}

3. srdz.preview.2.0.js

function ImgPreview(){}
 
ImgPreview.prototype.preview=function(options){
  
 var time = new Date().getTime();
 var fileid = "file" + time;
 var xdelid = "xdel" + time;
 var delid = "del" + time; 
 var viewid = "view" + time;
  
 var htm = "" +
 "<p>" +
  "</p><p>" +
   "<a>" +
    "<span>上传图片</span>" +
    "<input>" +
   "</a>" +
  "</p>" +
  "<p>" +
   "<a>" +
    "<span>删除图片</span>" +
    "<input>" +
   "</a>" +
  "</p>" +
 "" +
 "<p></p>";
  
 $("#" + options.previewid).html(htm);
  
 $("#" + fileid).bind("click",function(){
   
  var $this =$(this);
   
  var browser={
   isIE:function(ver){
    var b = document.createElement('b');
    b.innerHTML = '<!--[if IE &#39; + ver + &#39;]><i></i><![endif]-->';
    return b.getElementsByTagName('i').length === 1;
   }
  };
   
  $this.change(function(){
   var regex=/(.*)\.(jpg|jpeg|png)$/;
   var val = $this.val();
   if(!regex.test(val)){
    $("#" + viewid).html("<span>请选择正确的图片（jpg、jpeg、png）!</span>");
    return;
   }
    
   if(browser.isIE(6)){
    HanderOther($this);
   }else if(browser.isIE(7) || browser.isIE(8) || browser.isIE(9)){
    HanderIE789($this);
   }else if(window.FileReader){
    HanderFileReader($this);
   }else{
    $("#" + viewid).html("<span>该浏览器不支持预览图片!</span>");
   }
    
   function HanderFileReader($this){
    var oFReader = new window.FileReader(),
    rFilter = /^(?:image\/bmp|image\/cis\-cod|image\/gif|image\/ief|image\/jpeg|image\/jpeg|image\/jpeg|image\/pipeg|image\/png|image\/svg\+xml|image\/tiff|image\/x\-cmu\-raster|image\/x\-cmx|image\/x\-icon|image\/x\-portable\-anymap|image\/x\-portable\-bitmap|image\/x\-portable\-graymap|image\/x\-portable\-pixmap|image\/x\-rgb|image\/x\-xbitmap|image\/x\-xpixmap|image\/x\-xwindowdump)$/i;
    oFReader.onload = function (oFREvent){
     $("#" + viewid).html("<img  alt="Detailed explanation of image upload preview and deletion steps with JQuery" >");
     $("#" + xdelid).show();
    };
  
    var aFiles = $this.get(0).files;
    if (aFiles.length == 0) { return; }
    if (!rFilter.test(aFiles[0].type)) { 
     $("#" + viewid).html("<span>请选择正确的图片（jpg、jpeg、png）!</span>"); 
     return; 
    }
    oFReader.readAsDataURL(aFiles[0]);
   }
  
   function HanderIE789($this){
    if(options.width != null && parseInt(options.width) > 0){
     $("#" + viewid).css("width",options.width + "px");
    }else{
     $("#" + viewid).css("width","378px");
    }
    if(options.height != null && parseInt(options.height) > 0){
     $("#" + viewid).css("height",options.height + "px");
    }else{
     $("#" + viewid).css("height","358px");
    }
    $("#" + viewid).css("filter","progid:DXImageTransform.Microsoft.AlphaImageLoader(sizingMethod=scale,src='"+GetImgSrc($this)+"')");
    $("#" + xdelid).show();
   }
  
   function HanderOther($this){
    $("#" + viewid).html("<img  alt="Detailed explanation of image upload preview and deletion steps with JQuery" >");
    $("#" + xdelid).show();
   }
  
   function GetImgSrc($this){
    $this.select();
    $this.blur();
    var imgSrc =document.selection.createRange().text;
    document.selection.empty();
    return imgSrc;
   }
    
    
  });
 });//绑定按钮事件
  
 $("#" + delid).bind("click",function(){
  var browser={
    isIE:function(ver){
     var b = document.createElement('b');
     b.innerHTML = '<!--[if IE &#39; + ver + &#39;]><i></i><![endif]-->';
     return b.getElementsByTagName('i').length === 1;
    }
   };
   
  if(browser.isIE(7) || browser.isIE(8) || browser.isIE(9)){
   $("#" + fileid).val('');
   $("#" + viewid).css("filter","");
   $("#" + viewid).css("width","");
   $("#" + viewid).css("height","");
   $("#" + xdelid).hide();
  }else{
   $("#" + fileid).val('');
   $("#" + viewid).empty();
   $("#" + xdelid).hide();
  }
 });
};

I believe you have mastered the method after reading the case in this article. For more exciting information, please pay attention to other related articles on the php Chinese website!

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The above is the detailed content of Detailed explanation of image upload preview and deletion steps with JQuery. For more information, please follow other related articles on the PHP Chinese website!