一、将海报大图截屏部分图片并渲染页面
二、实现代码如下
<!DOCTYPE html>
<html lang="zh">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
</head>
<body>
<div>
<h1>图片上传后，截取一部分图片并渲染到页面</h1>
<input type="file" id="fileInput" />
<button id="uploadFile">上传文件</button>
<img id="sliceImg" style="display: none; ;" height="200px" width="300px"/>
</div>
<script>
document.getElementById('uploadFile').addEventListener('click', function() {
let fileInput = document.getElementById('fileInput');
let file = fileInput.files[0]
console.log('file', file)
let sliceImg = document.getElementById('sliceImg');
let file_slice=1024*50;//截取50kb 1kb=1024b
let sliceBlob = file.slice(0,file_slice,file.type);
let reader= new FileReader();
reader.onload=function(e){
sliceImg.src=e.target.result;
sliceImg.style.display='block'
}
reader.readAsDataURL(sliceBlob)
})
</script>
</body>
</html>
三、原图
