How to use the JAVASCRIPT_FUNCTION Component
Barcode to PC allows you to manipulate the barcodes and the variables by executing JavaScript code.
Examples of what you can do with this component
- Remove the first n characters from the barcode
- Remove the last n characters from the barcode
- Replace parts of the barcode
- Extrapolate the data encoded inside the barcode
and the list goes on and on, you can use pretty much any combination of JavaScript methods to manipulate the strings. You can find the full list here.
Setup
Step 1 – Add the JAVASCRIPT FUNCTION Component
To do that, Drag & Drop the component from the Available components field to the Output components field by keeping pressed the left mouse button.
Step 2 – Write the JavaScript Function
Click on the component that you just added, and type the function that you want to be executed inside the JavaScript field.
Step 3 – Add variables
Every time you use a variable inside the JavaScript field you’ll have to insert a corresponding Output Component that will assign a value to that variable.
For example if you use the barcode
variable, you’ll have to insert also a component in the Output template field, otherwise, if you don’t do that the JavaScript component will fail and won’t be executed properly.
To prevent the BARCODE component affecting the Keyboard Emulation output you can click on it and enable the Skip output option.
Examples
Example 1
Let’s say that you want to remove the first character of the barcode
Initial barcode: 0897654321
Final output: 897654321
Follow these steps:
- Add a
component just after the
component
- Add this code in the JavaScript field:
barcode.substr(1)
. - Enable the Skip output option of the
component
Example 2
Extrapolate parts of the barcode
Initial barcode: 433-0132-22
Final output: 0132
Use the same procedure of Example 1, but use this JavaScript code instead: barcode.split('-')[1]
Example 3
Replace a specific part of the barcode
Initial barcode: first_name:john;last_name:doe
Final output: name:john doe
Use the same procedure of Example 1, but use this JavaScript code instead: barcode.replace('first_name:','name:').replace('last_name:', ' ')
Tip 1: to remove a specific part of the barcode you can use the replace() method, and pass an empty string as second parameter, for example: barcode.replace('a', '')
Tip 2: you can use a regular expression as first parameter, for example barcode.replace(/w/gi, '')
will perform a global, case-insensitive replacement of the w character.
Example 4
Extract a parameter from an URL
Initial barcode: https://example.com/?user_id=123&tracking_id=RN015215156&order_id=456
Final output: RN015215156
Use the same procedure of Example 1, but use this JavaScript code instead:
new URL(barcode).searchParams.get('tracking_id')