I want to use a icon in placeholder
<input type="text" placeholder="xxx" />
In bootstrap icon I can use 
But in this icon I can not find the icon code.
I want to use a icon in placeholder
<input type="text" placeholder="xxx" />
In bootstrap icon I can use 
But in this icon I can not find the icon code.
You can get the code of the icon by checking the .css file of the font. If the icon you're are searching for is written like this
.oi[data-glyph=caret-right]:before { content:'\e02f'; }
Then the unicode in HTML will be written like this 
.
https://codepen.io/mlarabi/pen/QWpXNBR
In this example I used the CDN of Open Iconic (https://cdnjs.cloudflare.com/ajax/libs/open-iconic/1.1.1/font/css/open-iconic.min.css) and changed the font-family
of the placeholder
of the input
to use the Icons
font given by the CSS.
<link rel="stylesheet" href="https://use.fontawesome.com/releases/v5.8.1/css/solid.css">
<input type="text" placeholder=" Search" style="font-family: Arial, 'Font Awesome 5 Free'" />