?js画图开发库--mxgraph--[grid-网格.html]?
?
点击图形下方按钮：网格根据图形大小变化：
<!--[if IE]><meta http-equiv="X-UA-Compatible" content="IE=5,IE=9" ><![endif]-->
<!DOCTYPE html>
<html>
<head>
<meta http-equiv=Content-Type content="text/html;charset=utf-8">
<title>Grid example for mxGraph</title>
<!-- 如果本文件的包与src不是在同一个目录,就要将basepath设置到src目录下 -->
<script type="text/javascript">
mxBasePath = '../src';
</script>
<!-- 引入支持库文件 -->
<script type="text/javascript" src="../src/js/mxClient.js"></script>
<!-- 示例代码 -->
<script type="text/javascript">
//程序在此启动
function main(container)
{
// // 检测浏览器兼容性
if (!mxClient.isBrowserSupported())
{
mxUtils.error('Browser is not supported!', 200, false);
}
else
{
mxEvent.disableContextMenu(document.body);
//去锯齿效果
mxRectangleShape.prototype.crisp = true;
// 在容器中创建图形
var graph = new mxGraph(container);
graph.graphHandler.scaleGrid = true;
graph.setPanning(true);
// 默认右键下拉列表
new mxRubberband(graph);
// 动态地创建网格（需要画布）
(function()
{
try
{
var canvas = document.createElement('canvas');
canvas.style.position = 'absolute';
canvas.style.top = '0px';
canvas.style.left = '0px';
canvas.style.zIndex = -1;
graph.container.appendChild(canvas);
var ctx = canvas.getContext('2d');
// 过滤画布事件，修改画布作为容器
mxGraphViewIsContainerEvent = mxGraphView.prototype.isContainerEvent;
mxGraphView.prototype.isContainerEvent = function(evt)
{
return mxGraphViewIsContainerEvent.apply(this, arguments) ||
mxEvent.getSource(evt) == canvas;
};
var s = 0;
var gs = 0;
var tr = new mxPoint();
var w = 0;
var h = 0;
function repaintGrid()
{
if (ctx != null)
{
var bounds = graph.getGraphBounds();
var width = Math.max(bounds.x + bounds.width, graph.container.clientWidth);
var height = Math.max(bounds.y + bounds.height, graph.container.clientHeight);
var sizeChanged = width != w || height != h;
if (graph.view.scale != s || graph.view.translate.x != tr.x || graph.view.translate.y != tr.y ||
gs != graph.gridSize || sizeChanged)
{
tr = graph.view.translate.clone();
s = graph.view.scale;
gs = graph.gridSize;
w = width;
h = height;
// 根据需要清除背景
if (!sizeChanged)
{
ctx.clearRect(0, 0, w, h);
}
else
{
canvas.setAttribute('width', w);
canvas.setAttribute('height', h);
}
var tx = tr.x * s;
var ty = tr.y * s;
// 设定网格线的距离（以像素为单位）
var minStepping = graph.gridSize;
var stepping = minStepping * s;
if (stepping < minStepping)
{
var count = Math.round(Math.ceil(minStepping / stepping) / 2) * 2;
stepping = count * stepping;
}
var xs = Math.floor((0 - tx) / stepping) * stepping + tx;
var xe = Math.ceil(w / stepping) * stepping;
var ys = Math.floor((0 - ty) / stepping) * stepping + ty;
var ye = Math.ceil(h / stepping) * stepping;
xe += Math.ceil(stepping);
ye += Math.ceil(stepping);
var ixs = Math.round(xs);
var ixe = Math.round(xe);
var iys = Math.round(ys);
var iye = Math.round(ye);
// 绘制网格
ctx.strokeStyle = '#f6f6f6';
ctx.beginPath();
for (var x = xs; x <= xe; x += stepping)
{
x = Math.round((x - tx) / stepping) * stepping + tx;
