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neichen/FileReader-image-preview.html

Forked from Arguseye/FileReader-image-preview.html
Created December 17, 2023 08:54
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FileReader 解析Excel文件
Raw
FileReader-image-preview.html
<!doctype html>
<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: 100px; height: 100px;" 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="Image preview" /></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>
Raw
FileReader-xlsx.html
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>FileReader 解析Excel文件</title>
<!-- https://github.com/SheetJS/js-xlsx -->
<script src="./js/xlsx.full.min.js"></script>
</head>
<body>
<input type="file"onchange="importf(this)" />
<div id="demo"></div>
<script>
/*
FileReader共有4种读取方法：
1.readAsArrayBuffer(file)：将文件读取为ArrayBuffer。
2.readAsBinaryString(file)：将文件读取为二进制字符串
3.readAsDataURL(file)：将文件读取为Data URL，实现图片预览
4.readAsText(file, [encoding])：将文件读取为文本，encoding缺省值为'UTF-8'
*/
var wb;//读取完成的数据
var rABS = false; //是否将文件读取为二进制字符串
function importf(obj) {//导入
if(!obj.files) {
return;
}
var f = obj.files[0];
var reader = new FileReader();
var start = new Date();
reader.onload = function(e) {
var data = e.target.result;
if(rABS) {
wb = XLSX.read(btoa(fixdata(data)), {//手动转化
type: 'base64'
});
} else {
wb = XLSX.read(data, {
type: 'binary'
});
}
// 2000 * 10 数据大约消耗307ms
var end = new Date();
console.log('end' + (end - start));
console.log(XLSX.utils.sheet_to_json(wb.Sheets[wb.SheetNames[0]]));
//wb.SheetNames[0]是获取Sheets中第一个Sheet的名字
//wb.Sheets[Sheet名]获取第一个Sheet的数据
document.getElementById("demo").innerHTML= JSON.stringify( XLSX.utils.sheet_to_json(wb.Sheets[wb.SheetNames[0]]) );
};
if(rABS) {
reader.readAsArrayBuffer(f);
} else {
reader.readAsBinaryString(f);
}
}
function fixdata(data) { //文件流转BinaryString
var o = "",
l = 0,
w = 10240;
for(; l < data.byteLength / w; ++l) o += String.fromCharCode.apply(null, new Uint8Array(data.slice(l * w, l * w + w)));
o += String.fromCharCode.apply(null, new Uint8Array(data.slice(l * w)));
return o;
}
</script>
</body>
</html>
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