A canvas tag reference: The strokeRect function

About

RGraph is a JavaScript charts library based on HTML5 SVG and canvas. RGraph is mature (over 15 years old) and has a wealth of features making it an ideal choice to use for showing charts on your website.

Download

Get the latest version of RGraph (version 6.18, 1st June 2024) from the download page. You can read the changelog here. There's also older versions available, minified files and links to cdnjs.com hosted libraries.

License

RGraph can be used for free under the GPL or if that doesn't suit your situation there's an inexpensive (£129) commercial license available.

Arguments to the function
An example

The strokeRect function is used for drawing rectangles on your canvas. As the name would suggest it does not fill them - only drawing the outline. An important thing to remember is that this is not a path function - so you don't have to call the stroke function - when you call the strokeRect function it immediately draws a rectangle on your canvas. It uses the strokeStyle setting for the color to use.

Arguments to the function

The x-axis coordinate
The y-axis coordinate
The width of the rectangle
The height of the rectangle

An example

<script>
    window.onload = function ()
    {
        var canvas  = document.getElementById("cvs");
        var context = canvas.getContext('2d');

        var x       = 50;
        var y       = 50;
        var width   = 100;
        var height  = 100;
        
        context.strokeStyle = 'red';
        context.strokeRect(x, y, width, height);
    }
</script>