java web - 限制文件的上传类型为图片类型(.gif,.png,.jpg,.jpeg)

来源:互联网 发布:金蝶网络破解版 编辑:程序博客网 时间:2024/05/18 02:34

1.使用ajax

function insertTitle(tValue){if(tValue!=''){var len = tValue.length;var str = tValue.substr(tValue.lastIndexOf("."),len);if(str=='.jpg'||str=='.JPG'||str=='.gif'||str=='.GIF'||str=='.png'||str=='.PNG'||str=='.bmp'||str=='.BMP'){}else{parent.ymPrompt.alert({title:'信息提示',message:'请选择格式为 .jpg .JPG .gif .GIF .png .PNG .bmp .BMP的附件上传!',width:350,height:200});return false;}var file = document.getElementById("files");file.select();document.getElementById("picDiv").focus();var realPath = document.selection.createRange().text;document.getElementById("tupianpath").value = realPath;}}
相应的jsp是:

<input type="file" name="files" id="file1" style="cursor: pointer;position:absolute;filter:alpha(opacity=0);width:0;opacity: 0.0;/**" size="1"   onchange="if(this.value)insertPhoto(this.value,'1');" hidefocus/>


2.不使用ajax

function fileChange(target){  //检测上传文件的类型     var ext,idx;       if (target == ''){      ymPrompt.alert({title:'信息提示',message:'请选择需要上传的文件!',width:250,height:160});        return;     } else {           idx = target.lastIndexOf(".");           if (idx != -1){               ext = target.substr(idx+1).toUpperCase();               ext = ext.toLowerCase( );             if (ext!='jpg'&&ext!='png'&&ext!='jpeg'&& ext!='gif'){                ymPrompt.alert({title:'信息提示',message:'只能上传jpg,png,jpeg,gif类型的文件!',width:250,height:160});          document.getElementById("yingye").innerHTML="<input   name='file' id='yingyezhizhao'  class='text_172' type=file onchange=\"fileChange(this.value);\">";                   return;              }           } else {              return;        }       }}     </script>
相应的jsp为:
<input   name='file' id='yingyezhizhao'   type=file class="text_172" onchange="fileChange(this.value);" accept=".gif,.jpg,.jpeg,.png">


0 0