我正在开发一个插件,我将Image转换为Canvas并存储为数据url。此功能触发' load'事件,但我如何转换页面上已有的图像? (不要刷新页面或再次加载任何图像)。我尝试使用Filereader()函数,但这也适用于' onload'概念。那么当用户点击图像时如何将图像保存为数据网址呢?
image.addEventListener("load", function () {
var imgCanvas = document.createElement("canvas"),
imgContext = imgCanvas.getContext("2d");
imgCanvas.width = image.width;
imgCanvas.height = image.height;
imgContext.drawImage(image, 0, 0, image.width, image.height);
imgInfo = imgCanvas.toDataURL("image/png");
localStorage.setItem("imgInfo", imgInfo);
}, false);
答案 0 :(得分:4)
现在它完美无缺。如果您使用javascript创建临时图像元素,则将其存储在localStorage中。这对我有用,希望它能帮助别人
image = document.createElement('img');
document.body.appendChild(image);
image.setAttribute('style','display:none');
image.setAttribute('alt','script div');
image.setAttribute("src", path);
var imgCanvas = document.createElement("canvas"),
imgContext = imgCanvas.getContext("2d");
// Make sure canvas is as big as the picture
imgCanvas.width = image.width;
imgCanvas.height = image.height;
// Draw image into canvas element
imgContext.drawImage(image, 0, 0, image.width, image.height);
// Save image as a data URL
imgInfom = imgCanvas.toDataURL("image/png");
localStorage.setItem("imgInfo",imgInfom);
document.body.removeChild(image);
答案 1 :(得分:0)
您可以将点击侦听器绑定到图像,并在点击时保存data-url。
var img = document.getElementById("image");
img.addEventListener("click",function(){
var c = document.createElement("canvas");
var ctx = c.getContext("2d");
ctx.canvas.width = img.getAttribute("width");
ctx.canvas.height = img.getAttribute("height");
ctx.drawImage(img,0,0);
var imgInfo = c.toDataURL("image/png");
localStorage.setItem("imgInfo", imgInfo);
});