<<SPAN class=start-tag>script</SPAN><SPAN class=attribute-name> language</SPAN>=<SPAN class=attribute-value>"javascript" </SPAN><SPAN class=attribute-name>type</SPAN>=<SPAN class=attribute-value>"text/javascript"</SPAN>><br> var allowExt = ['jpg', 'gif', 'bmp', 'png', 'jpeg'];<br> var preivew = function(file, container){<br> try{<br> var pic = new Picture(file, container);<br> }catch(e){<br> alert(e);<br> }<br> }<br> //缩略图类定义<br> var Picture = function(file, container){<br> var height = 0, <br> widht = 0, <br> ext = '',<br> size = 0,<br> name = '',<br> path = '';<br> var self = this;<br> if(file){ <br> name = file.value;<br> if (window.navigator.userAgent.indexOf("MSIE")>=1){ <br> file.select(); <br> path = document.selection.createRange().text; <br> }else if(window.navigator.userAgent.indexOf("Firefox")>=1){ <br> if(file.files){ <br> path = file.files.item(0).getAsDataURL(); <br> }else{<br> path = file.value;<br> }<br> } <br> }else{<br> throw "bad file";<br> } <br><br><br> ext = name.substr(name.lastIndexOf("."), name.length);<br><br> if(container.tagName.toLowerCase() != 'img'){<br> throw "container is not a valid img label";<br> container.visibility = 'hidden';<br> }<br> container.src = path;<br> container.alt = name;<br> container.style.visibility = 'visible';<br> height = container.height;<br> widht = container.widht;<br> size = container.fileSize;<br><br><br> this.get = function(name){<br> return self[name];<br> }<br><br> this.isValid = function(){<br> if(allowExt.indexOf(self.ext) !== -1){<br> throw 'the ext is not allowed to upload';<br> return false;<br> }<br> }<br> }<br></<SPAN class=end-tag>script</SPAN>><br> <<SPAN class=start-tag>div</SPAN><SPAN class=attribute-name> class</SPAN>=<SPAN class=attribute-value>'previewDemo'</SPAN>><br> <<SPAN class=start-tag>input</SPAN><SPAN class=attribute-name> id</SPAN>=<SPAN class=attribute-value>"file" </SPAN><SPAN class=attribute-name>type</SPAN>=<SPAN class=attribute-value>"file" </SPAN><SPAN class=attribute-name>onchange</SPAN>=<SPAN class=attribute-value>"preivew(this, document.getElementById('img'));"</SPAN>><br> <<SPAN class=start-tag>img</SPAN><SPAN class=attribute-name> id</SPAN>=<SPAN class=attribute-value>"img" </SPAN><SPAN class=attribute-name>style</SPAN>=<SPAN class=attribute-value>"visibility:hidden" </SPAN><SPAN class=attribute-name>height</SPAN>=<SPAN class=attribute-value>"100px" </SPAN><SPAN class=attribute-name>width</SPAN>=<SPAN class=attribute-value>"100px"</SPAN>><br></<SPAN class=end-tag>div</SPAN>>