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Image Uploader
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| <!DOCTYPE html> | |
| <html lang="en"> | |
| <head> | |
| <meta charset="UTF-8"> | |
| <meta name="viewport" content="width=device-width, initial-scale=1.0"> | |
| <meta http-equiv="X-UA-Compatible" content="ie=edge"> | |
| <title>Image Uploader</title> | |
| </head> | |
| <body> | |
| <canvas id="canvas" style="border: solid 1px #cccccc" width="400" height="300"></canvas> | |
| <div class="upload"> | |
| <input type="file" name="file" id="file"> | |
| </div> | |
| <script> | |
| const canvas = document.querySelector('#canvas') | |
| const file = document.querySelector('#file') | |
| file.addEventListener('change', (e) => { | |
| const fileData = e.target.files[0] | |
| if (!fileData.type.match('image.*')) { | |
| alert('Choose an image') | |
| return | |
| } | |
| const reader = new FileReader() | |
| reader.onload = () => { | |
| const ctx = canvas.getContext('2d') | |
| const img = new Image() | |
| img.src = reader.result | |
| img.onload = function () { | |
| canvas.height = canvas.width * this.height / this.width | |
| ctx.drawImage(img, 0, 0, canvas.width, canvas.height) | |
| } | |
| } | |
| reader.readAsDataURL(fileData) | |
| }) | |
| </script> | |
| </body> | |
| </html> |
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