要构建一个具有标尺线、可打印且可调整纸张大小的在线设计编辑器，可以采用以下技术方案：
// 使用HTML5 Canvas或SVG作为绘图基础
const canvas = document.getElementById('design-canvas');
const ctx = canvas.getContext('2d');
// 或者使用SVG
const svg = document.createElementNS("http://www.w3.org/2000/svg", "svg");
document.getElementById('design-container').appendChild(svg);
// 水平标尺
function drawHorizontalRuler() {
const ruler = document.getElementById('horizontal-ruler');
const rulerCtx = ruler.getContext('2d');
// 设置标尺样式
rulerCtx.strokeStyle = '#999';
rulerCtx.font = '10px Arial';
rulerCtx.fillStyle = '#333';
// 绘制刻度
for (let i = 0; i < ruler.width; i += 10) {
if (i % 100 === 0) {
rulerCtx.fillText(i.toString(), i + 2, 10);
rulerCtx.beginPath();
rulerCtx.moveTo(i, 15);
rulerCtx.lineTo(i, 25);
rulerCtx.stroke();
} else if (i % 50 === 0) {
rulerCtx.beginPath();
rulerCtx.moveTo(i, 18);
rulerCtx.lineTo(i, 25);
rulerCtx.stroke();
} else {
rulerCtx.beginPath();
rulerCtx.moveTo(i, 22);
rulerCtx.lineTo(i, 25);
rulerCtx.stroke();
}
}
}
// 垂直标尺同理
// 纸张大小调整控件
document.getElementById('paper-size').addEventListener('change', function(e) {
const size = e.target.value.split('x');
const width = parseInt(size[0]);
const height = parseInt(size[1]);
// 更新画布尺寸
canvas.width = width;
canvas.height = height;
// 更新标尺
updateRulers();
// 重绘内容
redrawDesign();
});
// 自定义尺寸
document.getElementById('custom-size').addEventListener('click', function() {
const width = prompt('输入宽度(mm):');
const height = prompt('输入高度(mm):');
if (width && height) {
// 毫米转像素 (假设96dpi)
const pxWidth = Math.round(width * 3.779527559);
const pxHeight = Math.round(height * 3.779527559);
canvas.width = pxWidth;
canvas.height = pxHeight;
updateRulers();
redrawDesign();
}
});
// 打印功能
document.getElementById('print-btn').addEventListener('click', function() {
// 创建打印窗口
const printWindow = window.open('', '_blank');
// 获取设计内容
const designData = canvas.toDataURL('image/png');
// 构建打印内容
printWindow.document.write(`
<!DOCTYPE html>
<html>
<head>
<title>打印设计</title>
<style>
body { margin: 0; padding: 0; }
img { max-width: 100%; height: auto; }
</style>
</head>
<body>
<img src="${designData}" />
<script>
window.onload = function() {
setTimeout(function() {
window.print();
window.close();
}, 200);
};
</script>
</body>
</html>
`);
printWindow.document.close();
});
基础库选择:
UI框架:
打印优化:
class DesignEditor {
constructor(options) {
this.container = document.getElementById(options.containerId);
this.paperSize = options.defaultSize || { width: 800, height: 600 };
this.init();
}
init() {
this.createCanvas();
this.createRulers();
this.setupEventListeners();
this.drawGrid();
}
createCanvas() {
this.canvas = document.createElement('canvas');
this.canvas.width = this.paperSize.width;
this.canvas.height = this.paperSize.height;
this.canvas.style.border = '1px solid #ccc';
this.container.appendChild(this.canvas);
this.ctx = this.canvas.getContext('2d');
}
createRulers() {
// 创建水平和垂直标尺
this.hRuler = this.createRuler('horizontal');
this.vRuler = this.createRuler('vertical');
}
createRuler(orientation) {
const ruler = document.createElement('canvas');
ruler.className = `${orientation}-ruler`;
if (orientation === 'horizontal') {
ruler.width = this.paperSize.width;
ruler.height = 30;
} else {
ruler.width = 30;
ruler.height = this.paperSize.height;
}
this.container.appendChild(ruler);
return ruler;
}
drawGrid() {
// 绘制网格线
this.ctx.strokeStyle = '#eee';
this.ctx.lineWidth = 1;
// 水平线
for (let y = 0; y < this.paperSize.height; y += 20) {
this.ctx.beginPath();
this.ctx.moveTo(0, y);
this.ctx.lineTo(this.paperSize.width, y);
this.ctx.stroke();
}
// 垂直线
for (let x = 0; x < this.paperSize.width; x += 20) {
this.ctx.beginPath();
this.ctx.moveTo(x, 0);
this.ctx.lineTo(x, this.paperSize.height);
this.ctx.stroke();
}
}
setupEventListeners() {
// 实现拖拽、缩放等交互
// ...
}
updatePaperSize(width, height) {
this.paperSize = { width, height };
this.canvas.width = width;
this.canvas.height = height;
this.hRuler.width = width;
this.vRuler.height = height;
this.drawGrid();
this.updateRulers();
}
updateRulers() {
// 更新标尺刻度
// ...
}
exportAsImage() {
return this.canvas.toDataURL('image/png');
}
print() {
const printWindow = window.open('', '_blank');
printWindow.document.write(`
<!DOCTYPE html>
<html>
<head><title>打印设计</title></head>
<body>
<img src="${this.exportAsImage()}" style="max-width:100%;" />
<script>
window.onload = function() {
setTimeout(function() {
window.print();
window.close();
}, 200);
};
</script>
</body>
</html>
`);
printWindow.document.close();
}
}
// 使用示例
const editor = new DesignEditor({
containerId: 'editor-container',
defaultSize: { width: 800, height: 600 }
});
响应式标尺:
// 监听鼠标移动更新标尺指示线
canvas.addEventListener('mousemove', function(e) {
const rect = canvas.getBoundingClientRect();
const x = e.clientX - rect.left;
const y = e.clientY - rect.top;
updateRulerGuides(x, y);
});
多页面支持:
class Page {
constructor(width, height) {
this.width = width;
this.height = height;
this.elements = [];
}
addElement(element) {
this.elements.push(element);
}
}
class MultiPageEditor {
constructor() {
this.pages = [new Page(800, 600)];
this.currentPage = 0;
}
addPage(width, height) {
this.pages.push(new Page(width, height));
}
}
单位转换:
class UnitConverter {
static mmToPx(mm, dpi = 96) {
return mm * dpi / 25.4;
}
static pxToMm(px, dpi = 96) {
return px * 25.4 / dpi;
}
static cmToPx(cm, dpi = 96) {
return cm * dpi / 2.54;
}
}
requestAnimationFrame进行动画和重绘这个方案提供了构建在线设计编辑器的核心功能实现，您可以根据具体需求进行扩展和优化。