使用Javascript在div中绘制线条

Jas*_*els 1 html javascript canvas

使用画布,你可以用这样的javascript画一条线,

<html>
<canvas id="myCanvas" width="500" height="300" style="border:1px solid #d3d3d3;"></canvas>

<script>
var c=document.getElementById("myCanvas");
var ctx = c.getContext("2d");
ctx.moveTo(20,20);
ctx.lineTo(100,100);
ctx.stroke();
</script>
</html>
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我怎么能做同样的事情,但通过使用div标签而不是画布?我想这样做的原因是因为画布似乎不适用于IE,我知道Google图表使用div标签而不是画布来绘制图形,所以它可能是可能的.

我尝试用div替换画布,但它不起作用.

Ama*_*ian 7

使用Jquery:

<div id='rPaper'></div>
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jQuery的

 x1 = 50, y1 = 50,
 x2 = 350, y2 = 50;
 drawnode(x1, y1);
 drawnode(x2, y2);
 drawline(x1, y1, x2, y2);


 function drawnode(x, y) {

     var ele = ""
     var style = "";
     style += "position:absolute;";
     style += "z-index:100;"
     ele += "<div class='relNode' style=" + style + ">";
     ele += "<span> Test Node</span>"
     ele += "<div>"

     $('#rPaper').show();
     var node = $(ele).appendTo('#rPaper');
     var width = node.width();
     var height = node.height();

     var centerX = width / 2;
     var centerY = height / 2;

     var startX = x - centerX;
     var startY = y - centerY;

     node.css("left", startX).css("top", startY);

 }

 function drawline(ax, ay, bx, by) {
     console.log('ax: ' + ax);
     console.log('ay: ' + ay);
     console.log('bx: ' + bx);
     console.log('by: ' + by);


     if (ax > bx) {
         bx = ax + bx;
         ax = bx - ax;
         bx = bx - ax;
         by = ay + by;
         ay = by - ay;
         by = by - ay;
     }


     console.log('ax: ' + ax);
     console.log('ay: ' + ay);
     console.log('bx: ' + bx);
     console.log('by: ' + by);

     var angle = Math.atan((ay - by) / (bx - ax));
     console.log('angle: ' + angle);

     angle = (angle * 180 / Math.PI);
     console.log('angle: ' + angle);
     angle = -angle;
     console.log('angle: ' + angle);

     var length = Math.sqrt((ax - bx) * (ax - bx) + (ay - by) * (ay - by));
     console.log('length: ' + length);

     var style = ""
     style += "left:" + (ax) + "px;"
     style += "top:" + (ay) + "px;"
     style += "width:" + length + "px;"
     style += "height:1px;"
     style += "background-color:black;"
     style += "position:absolute;"
     style += "transform:rotate(" + angle + "deg);"
     style += "-ms-transform:rotate(" + angle + "deg);"
     style += "transform-origin:0% 0%;"
     style += "-moz-transform:rotate(" + angle + "deg);"
     style += "-moz-transform-origin:0% 0%;"
     style += "-webkit-transform:rotate(" + angle + "deg);"
     style += "-webkit-transform-origin:0% 0%;"
     style += "-o-transform:rotate(" + angle + "deg);"
     style += "-o-transform-origin:0% 0%;"
     style += "-webkit-box-shadow: 0px 0px 2px 2px rgba(0, 0, 0, .1);"
     style += "box-shadow: 0px 0px 2px 2px rgba(0, 0, 0, .1);"
     style += "z-index:99;"
     $("<div style='" + style + "'></div>").appendTo('#rPaper');
 }
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演示

// right top -> left bottom
    x1 = 850, y1 = 150,
    x2 = 550, y2 = 250;
drawnode(x1, y1);
drawnode(x2, y2);
drawline(x1, y1, x2, y2);
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演示

// right bottom -> left top
    x1 = 750, y1 = 150,
    x2 = 550, y2 = 50;
drawnode(x1, y1);
drawnode(x2, y2);
drawline(x1, y1, x2, y2);
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演示

// left top -> right bottom
    x1 = 150, y1 = 150,
    x2 = 350, y2 = 350;
drawnode(x1, y1);
drawnode(x2, y2);
drawline(x1, y1, x2, y2);
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演示

// vertical line: down -> up
    x1 = 150, y1 = 350,
    x2 = 150, y2 = 150;
drawnode(x1, y1);
drawnode(x2, y2);
drawline(x1, y1, x2, y2);
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演示