推荐一款H5生成海报利器html2canvas

npm install --save html2canvas

yarn add html2canvas

<script src="http://html2canvas.hertzen.com/dist/html2canvas.min.js"></script>

<div ref="picture">
    <h4>Hello world!</h4>
</div>

// 配置项
const config= {
    useCORS: true, // 使用跨域
};
html2canvas(this.$refs.picture, config).then((canvas) => {
    document.body.appendChild(canvas); // 自动在下方显示绘制的canvas图片
});

// 生成图片
creatImg() {
    const config= {
        useCORS: true, // 使用跨域
    };
    html2canvas(this.$refs.picture, config).then((canvas) => {
        const link = canvas.toDataURL("image/jpg");
        this.exportPicture(link, "文件名");
    });
}

// 导出图片
exportPicture(link, name = "未命名文件") {
    const file = document.createElement("a");
    file.style.display = "none";
    file.href = link;
    file.download = decodeURI(name);
    document.body.appendChild(file);
    file.click();
    document.body.removeChild(file);
}

<div id="capture" style="padding: 10px; background: #f5da55">
    <h4 style="color: #000; ">Hello world!</h4>
</div>

html2canvas(document.querySelector("#capture")).then(canvas => {
    let oImg = new Image();
    oImg.src = canvas.toDataURL();  // 导出图片
    document.body.appendChild(oImg);  // 将生成的图片添加到body
});

var opts = {

    useCORS: true // 【重要】开启跨域配置
};
html2canvas(document.querySelector("#capture"), opts).then(canvas => {
  document.body.appendChild(canvas);
});

html2canvas(document.querySelector("#capture"),{
   backgroundColor: null, //设置图片背景为透明
}).then(canvas => {
    let oImg = new Image();
    oImg.src = canvas.toDataURL();  // 导出图片
    document.body.appendChild(oImg);  // 将生成的图片添加到body
});