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Drawing line in a div with Javascript

With a canvas you can draw a line with javascript like this,

<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>

How can i do the same thing, but by using a div tag instead of a canvas? The reason i want to do this is beacuse the canvas does not seem to work on IE and i know that Google graphs make use of div tags and not canvases to draw graphs, so it might be possible.

I tried replacing the canvas with a div, but it does not work.

Using Jquery:

<div id='rPaper'></div>

Jquery

 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');
 }

Demo

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

Demo

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

Demo

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

Demo

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

Demo

Rendered some lines using div tag. Please refer below code

<div style="width: 112px; height: 47px; border-bottom: 1px solid black; -webkit-transform:   translateY(-20px) translateX(5px) rotate(27deg); position: absolute;/* top: -20px; */"></div>
<div style="width: 112px; height: 47px; border-bottom: 1px solid black; -webkit-transform: translateY(20px) translateX(5px) rotate(-26deg); position: absolute;top: -33px;left: -13px;"></div>

hope it helps.

fiddle link :

http://jsfiddle.net/NATnr/45/

Thanks,

Siva

您可以创建诸如p或div之类的标签,根据需要设置宽度,添加顶部边框并将其附加到要创建线的div中。

You can use CSS3 2D Transforms http://jsfiddle.net/dmRhL/ :

.line{
    width: 150px;
    transform: translate(50px,100px) rotate(30deg);
    -ms-transform: translate(50px,100px) rotate(30deg); /* IE 9 */
    -webkit-transform: translate(50px,100px) rotate(30deg); /* Safari and Chrome */
}

But looks like your problem is the old IE browsers that that will probably not help.

You can try using excanvas - a JS library that simulates the canvas element using IE's VML renderer.

Or some 2D drawing framework that will use canvas or SVG depending on browser support. You can find a full list at http://en.wikipedia.org/wiki/JavaScript_graphics_library

Other answers are very better than this... This uses PURE CSS, if you need.

<head>
<style>
#i1,#i2,#i3,#i4,#i5,#i6,#i7,#i8{border-right:2px solid black; height:2px;}
#i1{width:30px;}#i2{width:31px;}#i3{width:32px;}#i4{width:33px;}#i5{width:34px;}#i6{width:35px;}#i7{width:36px;}#i8{width:37px;}
</style>
</head>

<div id="i1"></div>
<div id="i2"></div>
<div id="i3"></div>
<div id="i4"></div>
<div id="i5"></div>
<div id="i6"></div>
<div id="i7"></div>
<div id="i8"></div>

And if you need to draw axis-parallel lines, you can put width or height as 1px and increase the other. fiddle here .

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