來自MOZILLA
DEVELOPER NETWORKhttps://developer.mozilla.org/en-US/docs/DOM/FileReader#readAsDataURL()
目前測試相容 IE9+、chrome、Firefox 10+
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"><html><head><meta content="text/html; charset=UTF-8" http-equiv="Content-Type" /><title>Image preview example</title><script type="text/javascript">oFReader = new 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) { document.getElementById("uploadPreview").src = oFREvent.target.result;}; function loadImageFile() { if (document.getElementById("uploadImage").files.length === 0) { return; } var oFile = document.getElementById("uploadImage").files[0]; if (!rFilter.test(oFile.type)) { alert("You must select a valid image file!"); return; } oFReader.readAsDataURL(oFile);}</script></head> <body onload="loadImageFile();"> <form name="uploadForm"> <table> <tbody> <tr> <td><img id="uploadPreview" style="width: 400px; height: 400px;" src="data:image/svg+xml,%3C%3Fxml%20version%3D%221.0%22%3F%3E%0A%3Csvg%20width%3D%22153%22%20height%3D%22153%22%20xmlns%3D%22http%3A//www.w3.org/2000/svg%22%3E%0A%20%3Cg%3E%0A%20%20%3Ctitle%3ENo%20image%3C/title%3E%0A%20%20%3Crect%20id%3D%22externRect%22%20height%3D%22150%22%20width%3D%22150%22%20y%3D%221.5%22%20x%3D%221.500024%22%20stroke-width%3D%223%22%20stroke%3D%22%23666666%22%20fill%3D%22%23e1e1e1%22/%3E%0A%20%20%3Ctext%20transform%3D%22matrix%286.66667%2C%200%2C%200%2C%206.66667%2C%20-960.5%2C%20-1099.33%29%22%20xml%3Aspace%3D%22preserve%22%20text-anchor%3D%22middle%22%20font-family%3D%22Fantasy%22%20font-size%3D%2214%22%20id%3D%22questionMark%22%20y%3D%22181.249569%22%20x%3D%22155.549819%22%20stroke-width%3D%220%22%20stroke%3D%22%23666666%22%20fill%3D%22%23000000%22%3E%3F%3C/text%3E%0A%20%3C/g%3E%0A%3C/svg%3E" alt="圖片預覽地區" /></td> <td><input id="uploadImage" type="file" name="myPhoto" onchange="loadImageFile();" /></td> </tr> </tbody> </table> <p><input type="submit" value="Send" /></p> </form></body></html>
熟悉JavaScript的,可以寫寫多張圖片預覽