How to create a rectangle canvas using Fabric.js ?

Last Updated : 12 May, 2020

In this article, we are going to create a canvas rectangle using FabricJS. The canvas rectangle means rectangle is movable and can be stretched according to requirement. Further, the rectangle can be customized when it comes to initial stroke color, height, width, fill color or stroke width.

Approach: To make this possible we are going to use a JavaScript library called FabricJS. After importing the library, we will create a canvas block in the body tag which will contain the rectangle. After this, we will initialize instances of Canvas and Rect provided by FabricJS and render the Rect instance on the Canvas instance as given in the example below.

Syntax:

fabric.Rect({
    width: number,
    height: number,
    fill: string,
    stroke: string,
    strokeWidth: int
});

Parameters: This function accepts five parameters as mentioned above and described below:

width: It specifies the width of rectangle.
height: It specifies the height of rectangle.
fill: It specifies the fill colour.
stroke: It specifies the stroke colour.
strokeWidth: It specifies the width of stroke.

Example: This example uses FabricJS to create simple editable canvas rectangle.

<!DOCTYPE html> 
<html> 
  
<head> 
    <title> 
        How to create a rectangle 
        canvas using Fabric.js ? 
    </title> 
      
    <!-- Adding the FabricJS library -->
    <script src= 
"https://cdnjs.cloudflare.com/ajax/libs/fabric.js/3.6.2/fabric.min.js"> 
    </script> 
</head> 
  
<body> 
    <canvas id="canvas" width="600" height="200"
        style="border:1px solid #000000"> 
    </canvas> 
      
    <script> 
      
        // Initiate a Canvas instance 
        var canvas = new fabric.Canvas("canvas"); 
  
        // Initiate a Rect instance 
        var rectangle = new fabric.Rect({ 
            width: 200, 
            height: 100, 
            fill: '', 
            stroke: 'green', 
            strokeWidth: 3 
        }); 
  
        // Render the Rect in canvas 
        canvas.add(rectangle); 
    </script> 
</body> 
  
</html> 