是否有一种方法将html渲染成PNG那样的图像?我知道这是可能的与画布,但我想渲染标准的html元素,如div为例。
当前回答
这就是我所做的。
注意:请检查App.js的代码。
链接到源代码
如果你喜欢它,你可以掉一颗星。✌️
更新:
import * as htmlToImage from 'html-to-image';
import download from 'downloadjs';
import logo from './logo.svg';
import './App.css';
const App = () => {
const onButtonClick = () => {
var domElement = document.getElementById('my-node');
htmlToImage.toJpeg(domElement)
.then(function (dataUrl) {
console.log(dataUrl);
download(dataUrl, 'image.jpeg');
})
.catch(function (error) {
console.error('oops, something went wrong!', error);
});
};
return (
<div className="App" id="my-node">
<header className="App-header">
<img src={logo} className="App-logo" alt="logo" />
<p>
Edit <code>src/App.js</code> and save to reload.
</p>
<a
className="App-link"
href="https://reactjs.org"
target="_blank"
rel="noopener noreferrer"
>
Learn React
</a><br></br>
<button onClick={onButtonClick}>Download as JPEG</button>
</header>
</div>
);
}
export default App;
其他回答
仅用JavaScript无法100%准确地做到这一点。
有一个Qt Webkit工具,还有一个python版本。如果你想自己做,我已经成功地用可可:
[self startTraverse:pagesArray performBlock:^(int collectionIndex, int pageIndex) {
NSString *locale = [self selectedLocale];
NSRect offscreenRect = NSMakeRect(0.0, 0.0, webView.frame.size.width, webView.frame.size.height);
NSBitmapImageRep* offscreenRep = nil;
offscreenRep = [[NSBitmapImageRep alloc] initWithBitmapDataPlanes:nil
pixelsWide:offscreenRect.size.width
pixelsHigh:offscreenRect.size.height
bitsPerSample:8
samplesPerPixel:4
hasAlpha:YES
isPlanar:NO
colorSpaceName:NSCalibratedRGBColorSpace
bitmapFormat:0
bytesPerRow:(4 * offscreenRect.size.width)
bitsPerPixel:32];
[NSGraphicsContext saveGraphicsState];
NSGraphicsContext *bitmapContext = [NSGraphicsContext graphicsContextWithBitmapImageRep:offscreenRep];
[NSGraphicsContext setCurrentContext:bitmapContext];
[webView displayRectIgnoringOpacity:offscreenRect inContext:bitmapContext];
[NSGraphicsContext restoreGraphicsState];
// Create a small + large thumbs
NSImage *smallThumbImage = [[NSImage alloc] initWithSize:thumbSizeSmall];
NSImage *largeThumbImage = [[NSImage alloc] initWithSize:thumbSizeLarge];
[smallThumbImage lockFocus];
[[NSGraphicsContext currentContext] setImageInterpolation:NSImageInterpolationHigh];
[offscreenRep drawInRect:CGRectMake(0, 0, thumbSizeSmall.width, thumbSizeSmall.height)];
NSBitmapImageRep *smallThumbOutput = [[NSBitmapImageRep alloc] initWithFocusedViewRect:CGRectMake(0, 0, thumbSizeSmall.width, thumbSizeSmall.height)];
[smallThumbImage unlockFocus];
[largeThumbImage lockFocus];
[[NSGraphicsContext currentContext] setImageInterpolation:NSImageInterpolationHigh];
[offscreenRep drawInRect:CGRectMake(0, 0, thumbSizeLarge.width, thumbSizeLarge.height)];
NSBitmapImageRep *largeThumbOutput = [[NSBitmapImageRep alloc] initWithFocusedViewRect:CGRectMake(0, 0, thumbSizeLarge.width, thumbSizeLarge.height)];
[largeThumbImage unlockFocus];
// Write out small
NSString *writePathSmall = [issueProvider.imageDestinationPath stringByAppendingPathComponent:[NSString stringWithFormat:@"/%@-collection-%03d-page-%03d_small.png", locale, collectionIndex, pageIndex]];
NSData *dataSmall = [smallThumbOutput representationUsingType:NSPNGFileType properties: nil];
[dataSmall writeToFile:writePathSmall atomically: NO];
// Write out lage
NSString *writePathLarge = [issueProvider.imageDestinationPath stringByAppendingPathComponent:[NSString stringWithFormat:@"/%@-collection-%03d-page-%03d_large.png", locale, collectionIndex, pageIndex]];
NSData *dataLarge = [largeThumbOutput representationUsingType:NSPNGFileType properties: nil];
[dataLarge writeToFile:writePathLarge atomically: NO];
}];
希望这能有所帮助!
请允许我推荐dom-to-image库,这是专门用来解决这个问题的(我是维护者)。 下面是你如何使用它(更多):
var node = document.getElementById('my-node');
domtoimage.toPng(node)
.then (function (dataUrl) {
var img = new Image();
img.src = dataUrl;
document.appendChild(img);
})
.catch(function (error) {
console.error('oops, something went wrong!', error);
});
你可以使用PhantomJS,这是一个无头webkit (safari和chrome(直到最近)的渲染引擎)驱动程序。您可以在这里学习如何对页面进行屏幕捕获。希望有帮助!
使用html2canvas只包括插件和调用方法,将HTML转换为画布,然后下载为PNG图像
html2canvas(document.getElementById("image-wrap")).then(function(canvas) {
var link = document.createElement("a");
document.body.appendChild(link);
link.download = "manpower_efficiency.jpg";
link.href = canvas.toDataURL();
link.target = '_blank';
link.click();
});
来源:http://www.freakyjolly.com/convert-html-document-into-image-jpg-png-from-canvas/
我推荐这个npm包“html-to-image”
描述: ✂️使用HTML5画布和SVG从DOM节点生成图像。
使用方法:
安装
npm install --save html-to-image
使用
/* ES6 */
import * as htmlToImage from 'html-to-image';
import { toPng, toJpeg, toBlob, toPixelData, toSvg } from 'html-to-image';
获取一个PNG图像base64编码的数据URL并下载它(使用download):
htmlToImage.toPng(document.getElementById('my-node'))
.then(function (dataUrl) {
download(dataUrl, 'my-node.png');
});