H5 Input=file 文件类型大小限制

 1 <html>
 2 <head>
 3     <meta charset="UTF-8">
 4     <title>Document</title>
 5 </head>
 6 <body>
 7 <input type="file" name="contractFileName" style=" 500px;" onchange="fileChange(this);"/>
 8 
 9 <script type="text/javascript">
10     var isIE = /msie/i.test(navigator.userAgent) && !window.opera;
11     function fileChange(target,id) {
12         var fileSize = 0;
13         var filetypes =[".jpg",".png",".rar",".txt",".zip",".doc",".ppt",".xls",".pdf",".docx",".xlsx"];
14         var filepath = target.value;
15         var filemaxsize = 1024*2;//2M
16         if(filepath){
17             var isnext = false;
18             var fileend = filepath.substring(filepath.lastIndexOf("."));
19             if(filetypes && filetypes.length>0){
20                 for(var i =0; i<filetypes.length;i++){
21                     if(filetypes[i]==fileend){
22                         isnext = true;
23                         break;
24                     }
25                 }
26             }
27             if(!isnext){
28                 alert("不接受此文件类型！");
29                 target.value ="";
30                 return false;
31             }
32         }else{
33             return false;
34         }
35         if (isIE && !target.files) {
36             var filePath = target.value;
37             var fileSystem = new ActiveXObject("Scripting.FileSystemObject");
38             if(!fileSystem.FileExists(filePath)){
39                 alert("附件不存在，请重新输入！");
40                 return false;
41             }
42             var file = fileSystem.GetFile (filePath);
43             fileSize = file.Size;
44         } else {
45             fileSize = target.files[0].size;
46         }
47 
48         var size = fileSize / 1024;
49         if(size>filemaxsize){
50             alert("附件大小不能大于"+filemaxsize/1024+"M！");
51             target.value ="";
52             return false;
53         }
54         if(size<=0){
55             alert("附件大小不能为0M！");
56             target.value ="";
57             return false;
58         }
59     }
60 </script>
61 
62 </body>
63 </html>