Bootstrap download icon button to link to pdf

To trigger a file download on a button click we will use a custom function or HTML 5 download attribute.
Approach 1: Using Download attribute 
The download attribute simply uses an anchor tag to prepare the location of the file that needs to be downloaded. The name of the file can be set using the attribute value name, if not provided then the original filename will be used.
Syntax 
 

filename: attribute specifies the name for the file that will be downloaded.
Example: 
 

Output: 
 

Approach 2: Using a custom javascript function 
 

• firstly made a textarea where all the text input will be issued.
• make an anchor tag using createElement property and then assigning it the download and href attribute.
• encodeURIComponent will encode everything with special meaning, so you use it for components of URIs. 
  For example, if we have text like “Hello: Geek ?”, there are special characters in this, so encodeURIComponent will encode them and append it for further usage.
• data:text/plain; charset=utf-8 is the attribute value of href (like href=” “), it specifies that the value must be of type text and with UTF-8 type encoding. The click() method simulates a mouse-click on an element.
• After that we simply call our download function with the text from textarea and our file name “GFG.txt” as parameters on the input button with id ‘btn’.

Example: 
 

Output: 
 

Approach 3: Using a custom javascript function with Axios Library
In this example, we will download images and file using Axios. This requires a little intermediate knowledge of the JavaScript to work and in this example a Axios library will be used.