How to check if an Image has crop applied using FabricJS?

FabricJS Javascript HTML5 Canvas

In this tutorial, we are going to show how you can check if an Image has crop applied using FabricJS. We can create an Image object by creating an instance of fabric.Image. Since it is one of the basic elements of FabricJS, we can also easily customize it by applying properties like angle, opacity etc. In order to find whether an Image has crop applied, we use the hasCrop method. This method returns false in case of crop is not applied, or the applied crop value in case if it is applied.

Syntax

hasCrop(): Boolean | Number

Using the hasCrop method

Example

In this example, we have used the hasCrop method to find whether the Image object has crop applied. In this case, our image object does not have any image cropping due to which the logged output is false.


<!DOCTYPE html>
<html>
<head>
   <!-- Adding the Fabric JS Library-->
   <script src="https://cdnjs.cloudflare.com/ajax/libs/fabric.js/510/fabric.min.js"></script>
</head>
<body>
   <h2>Using the hasCrop method</h2>
   <p>
      You can open the console from dev tools to see that the logged output is false
   </p>
   <canvas id="canvas"></canvas>
   <img src="https://www.tutorialspoint.com/images/logo.png" id="img1" style="display: none" />
   <script>
      // Initiate a canvas instance
      var canvas = new fabric.Canvas("canvas");
      canvas.setWidth(document.body.scrollWidth);
      canvas.setHeight(250);
      
      // Initiating the image element
      var imageElement = document.getElementById("img1");
      
      // Initiate an Image object
      var image = new fabric.Image(imageElement, {
         top: 50,
         left: 110,
      });
      
      // Add it to the canvas
      canvas.add(image);
      
      // Using the hasCrop method
      console.log("Is crop applied for the Image object?: ", image.hasCrop());
   </script>
</body>
</html>

Using the hasCrop method along with cropY property

Example

Let’s see a code example of the logged output when the hasCrop method is used along with the cropY property. We have passed the cropY property a value of 2 which will ensure that the image object has a 2px image crop in the Y-direction. In this case, the crop value is returned in the console.


<!DOCTYPE html>
<html>
<head>
   <!-- Adding the Fabric JS Library-->
   <script src="https://cdnjs.cloudflare.com/ajax/libs/fabric.js/510/fabric.min.js"></script>
</head>
<body>
   <h2>Using the hasCrop method along with cropY property</h2>
   <p>
      You can open the console from dev tools to see that the logged output is 2
   </p>
   <canvas id="canvas"></canvas>
   <img src="https://www.tutorialspoint.com/images/logo.png" id="img1" style="display: none" />
   <script>
      // Initiate a canvas instance
      var canvas = new fabric.Canvas("canvas");
      canvas.setWidth(document.body.scrollWidth);
      canvas.setHeight(250);
      
      // Initiating the image element
      var imageElement = document.getElementById("img1");
      
      // Initiate an Image object
      var image = new fabric.Image(imageElement, {
         top: 50,
         left: 110,
         cropY: 2,
      });
      
      // Add it to the canvas
      canvas.add(image);
      
      // Using the hasCrop method
      console.log(
         "Crop value applied for the Image object is: ",
         image.hasCrop()
      );
   </script>
</body>
</html>

Conclusion

In this tutorial, we used two examples to demonstrate how you can check if an Image has crop applied using FabricJS.

Rahul Gurung

Updated on: 26-Oct-2022

179 Views

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