1.效果如下，可测试
2.代码如下
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title>无标题文档</title> <script type="text/javascript"> //本地图片预览 function setImagePreview(fieldupload, image, imagediv) { var docObj = document.getElementById(fieldupload); var imgObjPreview = document.getElementById(image); if (docObj.files && docObj.files[0]) { //火狐下，直接设img属性 imgObjPreview.style.display = ‘block‘; imgObjPreview.style.width = ‘150px‘; imgObjPreview.style.height = ‘150px‘; //imgObjPreview.src = docObj.files[0].getAsDataURL(); //火狐7以上版本不能用上面的getAsDataURL()方式获取，需要一下方式 imgObjPreview.src = window.URL.createObjectURL(docObj.files[0]); } else { //IE下，使用滤镜 docObj.select(); var imgSrc = document.selection.createRange().text; var localImagId = document.getElementById(imagediv); //必须设置初始大小 localImagId.style.width = "150px"; localImagId.style.height = "150px"; //图片异常的捕捉，防止用户修改后缀来伪造图片 try { localImagId.style.filter = "progid:DXImageTransform.Microsoft.AlphaImageLoader(sizingMethod=scale)"; localImagId.filters.item("DXImageTransform.Microsoft.AlphaImageLoader").src = imgSrc; } catch (e) { alert("您上传的图片格式不正确，请重新选择!"); return false; } imgObjPreview.style.display = ‘none‘; document.selection.empty(); } return true; } </script> </head> <body> <div id="localImag"> <img id="preview" width="150px" height="150px" src="http://image.bubuko.com/info/201404/20180110153821132089.gif" alt="" /></div> <div> <input type="file" onchange="javascript:setImagePreview(‘upload‘,‘preview‘,‘localImag‘);" id="upload" /> </div> </body> </html>
原文：http://www.cnblogs.com/yc-755909659/p/3640801.html