I have written this code as illustrated in
saving-html-5-canvas-as-image-on-the-server-using-aspnet
Default.aspx
<script src="http://ajax.aspnetcdn.com/ajax/jQuery/jquery-1.4.2.min.js" type="text/javascript"></script>
<script type="text/Javascript" language="Javascript">
function drawShapes() {
var canvas = document.getElementById("myCanvas");
var context = canvas.getContext("2d");
context.fillStyle = "Blue";
context.fillRect(0, 0, 200, 200);
context.beginPath();
context.lineWidth = "4";
context.strokeStyle = "Green";
context.fillStyle = "Yellow";
context.arc(150, 100, 50, 20, Math.PI * 2, false);
context.stroke();
context.fill();
}
</script>
<body onload="drawShapes()">
<div>
<canvas id="myCanvas" width="200" height="200"></canvas>
<input type="button" id="btnSave" name="btnSave" value="Save the canvas to server" />
<script type="text/javascript">
$(function() {
$("#btnSave").click(function() {
var image = document.getElementById("myCanvas").toDataURL("image/png");
image = image.replace('data:image/png;base64,', '');
$.ajax({
type: 'POST',
url: 'CanvasSave.aspx/UploadImage',
data: '{ "imageData" : "' + image + '" }',
contentType: 'application/json; charset=utf-8',
dataType: 'json',
success: function(msg) {
alert('Image saved successfully !');
}
});
});
});
</script>
</div>
Default.aspx.cs
using System;
using System.IO;
using System.Web.Script.Services;
using System.Web.Services;
[ScriptService]
public partial class _Default : System.Web.UI.Page
{
static string path = @"F:\Dinesh\";
[WebMethod()]
public static void UploadImage(string imageData)
{
string fileNameWitPath = path + DateTime.Now.ToString().Replace("/", "-").Replace(" ", "- ").Replace(":", "") + ".png";
using (FileStream fs = new FileStream(fileNameWitPath, FileMode.Create))
{
using (BinaryWriter bw = new BinaryWriter(fs))
{
byte[] data = Convert.FromBase64String(imageData);
bw.Write(data);
bw.Close();
}
}
}
}
Now, drawShapes() is working and I can see the graphics in canvas when view in browser. But when I click the button to save that canvas image in folder nothing is happen. How can I save that canvas image in my folder?
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