构建一个支持标尺、打印和可调纸张大小的在线可视化设计编辑器涉及多个技术组件和步骤。以下是一个高层次的指南，帮助你理解如何实现这样的系统：
实现思路:
代码示例:
const canvas = new fabric.Canvas('canvas');
const rulerX = document.getElementById('ruler-x');
const rulerY = document.getElementById('ruler-y');
canvas.on('mouse:move', function(event) {
const pointer = canvas.getPointer(event.e);
rulerX.innerHTML = `X: ${pointer.x}`;
rulerY.innerHTML = `Y: ${pointer.y}`;
});
实现思路:
window.print())。代码示例:
function printCanvas() {
const printWindow = window.open('', '_blank');
printWindow.document.write('<html><head><title>Print</title></head><body>');
printWindow.document.write('<img src="' + canvas.toDataURL() + '" />');
printWindow.document.write('</body></html>');
printWindow.document.close();
printWindow.print();
}
实现思路:
代码示例:
function resizeCanvas(width, height) {
canvas.setWidth(width);
canvas.setHeight(height);
canvas.renderAll();
}
document.getElementById('paper-size').addEventListener('change', function(event) {
const size = event.target.value.split('x');
resizeCanvas(parseInt(size[0]), parseInt(size[1]));
});
实现思路:
代码示例:
const socket = new WebSocket('ws://yourserver.com');
socket.onmessage = function(event) {
const data = JSON.parse(event.data);
canvas.loadFromJSON(data, canvas.renderAll.bind(canvas));
};
function saveCanvas() {
const json = JSON.stringify(canvas);
socket.send(json);
}
通过以上步骤，你可以构建一个功能完善的在线可视化设计编辑器。每个步骤都需要详细的设计和实现，但遵循这个指南可以帮助你系统地完成项目。