- Go to Solution Explorer
- Right-click on the Application name
- Select Add-->add new item
- Now in the window that opens, select an HTML page or new Web form
- Rename it to canvasgraphicalequation.aspx
![canvasg1.png]()
Step 2 : In this section we will create the style for the media and create the .css on the media screen. Put the given script in the Head section of the HTML or between the <head>--</head> tags. Here the CSS is used for design purposes.
CSS Script
<style>
body
{
margin: 0px;
padding: 0px;
}
Canvas
{
border: 2px solid #9C9898;
margin-top: 50px;
margin-left: 50px;
background-color: #F4D19F;
box-shadow: 5px 5px 8px #222;
}
.title
{
text-align: center;
font-family: Segoe UI Light, Arial, Helvetica;
font-size: 2.2em;
margin: 1em;
}
.info
{
text-align: center;
font-family: Segoe UI Light, Arial, Helvetica;
font-size: 1.2em;
margin: 0.25em;
}
</style>
Step 3 : In this part we need to work on some JavaScript. To fully understand how JavaScript works, download the attached .rar file and run the CanvasGraphEquation application.
The whole JavaScript looks as in the following:
<script>
function Graph(config)
{
// user defined properties
this.canvas = document.getElementById(config.canvasId);
this.minX = config.minX;
this.minY = config.minY;
this.maxX = config.maxX;
this.maxY = config.maxY;
this.unitsPerTick = config.unitsPerTick;
// constants
this.axisColor = "#aaa";
this.font = "8pt Calibri";
this.tickSize = 20;
// relationships
this.context = this.canvas.getContext("2d");
this.rangeX = this.maxX - this.minX;
this.rangeY = this.maxY - this.minY;
this.unitX = this.canvas.width / this.rangeX;
this.unitY = this.canvas.height / this.rangeY;
this.centerY = Math.round(Math.abs(this.minY / this.rangeY) * this.canvas.height);
this.centerX = Math.round(Math.abs(this.minX / this.rangeX) * this.canvas.width);
this.iteration = (this.maxX - this.minX) / 1000;
this.scaleX = this.canvas.width / this.rangeX;
this.scaleY = this.canvas.height / this.rangeY;
// draw x and y axis
this.drawXAxis();
this.drawYAxis();
}
Graph.prototype.drawXAxis = function ()
{
var context = this.context;
context.save();
context.beginPath();
context.moveTo(0, this.centerY);
context.lineTo(this.canvas.width, this.centerY);
context.strokeStyle = this.axisColor;
context.lineWidth = 2;
context.stroke();
// draw tick marks
var xPosIncrement = this.unitsPerTick * this.unitX;
var xPos, unit;
context.font = this.font;
context.textAlign = "center";
context.textBaseline = "top";
// draw left tick marks
xPos = this.centerX - xPosIncrement;
unit = -1 * this.unitsPerTick;
while (xPos > 0)
{
context.moveTo(xPos, this.centerY - this.tickSize / 2);
context.lineTo(xPos, this.centerY + this.tickSize / 2);
context.stroke();
context.fillText(unit, xPos, this.centerY + this.tickSize / 2 + 3);
unit -= this.unitsPerTick;
xPos = Math.round(xPos - xPosIncrement);
}
// draw right tick marks
xPos = this.centerX + xPosIncrement;
unit = this.unitsPerTick;
while (xPos < this.canvas.width)
{
context.moveTo(xPos, this.centerY - this.tickSize / 2);
context.lineTo(xPos, this.centerY + this.tickSize / 2);
context.stroke();
context.fillText(unit, xPos, this.centerY + this.tickSize / 2 + 3);
unit += this.unitsPerTick;
xPos = Math.round(xPos + xPosIncrement);
}
context.restore();
};
window.onload = function ()
{
var myGraph = new Graph({
canvasId: "myCanvas",
minX: -10,
minY: -10,
maxX: 10,
maxY: 10,
unitsPerTick: 1
});
myGraph.drawEquation(function (x)
{
return 5 * Math.sin(x);
}, "yellow", 3);
myGraph.drawEquation(function (x)
{
return x * x;
}, "orange", 3);
myGraph.drawEquation(function (x)
{
return 1 * x;
}, "green", 3);
};
</script>
Step 4 : In this section we are going to become familiar with the body part of HTML scripting. Replace this script from the body section of the canvasgraphicalequation.aspx page. Here we pass a Canvas in the canvas tag.
<body style="background-color: #C9E0E6">
<center>
<h1>
Canvas Graphical Equation Representation
</h1>
</center>
<hr />
<canvas id="myCanvas" width="578" height="300">
</canvas>
</body>
Step 5 : The complete code for the CanvasGraphEquation application.
<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="canvasgraphicalequation.aspx.cs" Inherits="CanvasGraphEquation._Default" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<style>
</style>
<script>
</script>
</head>
<body style="background-color: #C9E0E6">
<center>
<h1>
Canvas Graphical Equation Representation
</h1>
</center>
<hr />
<canvas id="myCanvas" width="578" height="300">
</canvas>
</body>
</html>
Step 6 : Output Press F5
Note : For the accurate output of HTML5 applications, you must have the Google Chrome browser in your PC. A Graphical equation displays when the application runs on the browser.
![canvasg.png]()
Here are the some useful resources
Canvas Scaling Animation Using HTML 5
Canvas Reset Transform Using HTML 5
Canvas Anchor Points Using HTML 5
Canvas Animated Positioning Using HTML 5
Canvas Mirror Transform Using HTML 5