react-katex
Display math expressions with KaTeX and React
Installation
$ npm install react-katex
# or
$ yarn add react-katexUsage
import 'katex/dist/katex.min.css';
import { InlineMath, BlockMath } from 'react-katex';InlineMath
Display math in the middle of the text.
var InlineMath = ReactKaTeX.InlineMath;
ReactDOM.render(<InlineMath math="\\int_0^\\infty x^2 dx"/>,
document.getElementById('math'));
// or
ReactDOM.render(<InlineMath>\int_0^\infty x^2 dx</InlineMath>,
document.getElementById('math'));It will be rendered like this:
BlockMath
Display math in a separated block, with larger font and symbols.
var BlockMath = ReactKaTeX.BlockMath;
ReactDOM.render(<BlockMath math="\\int_0^\\infty x^2 dx"/>,
document.getElementById('math'));
// or
ReactDOM.render(<BlockMath>\int_0^\infty x^2 dx</BlockMath>,
document.getElementById('math'));It will be rendered like this:
Note:
Don't forget to import KaTeX CSS file.
import 'katex/dist/katex.min.css';Error handling
Default error message
By default the error rendering is handled by KaTeX. You can optionally pass errorColor (defaults to #cc0000) as a prop:
var BlockMath = ReactKaTeX.BlockMath;
ReactDOM.render(
<BlockMath
math={'\\int_0^\\infty x^2 dx \\inta'}
errorColor={'#cc0000'}
/>, document.getElementById('math'));This will be rendered like so:
Custom error message
It's possible to handle parse errors using the prop renderError. This prop must be a function that receives the error object and returns what should be rendered when parsing fails:
var BlockMath = ReactKaTeX.BlockMath;
ReactDOM.render(
<BlockMath
math="\\int_{"
renderError={(error) => {
return <b>Fail: {error.name}</b>
}}
/>,
document.getElementById('math'));
// The code above will render '<b>Fail: ParseError</b>' because it's the value returned from `renderError`.This will render <b>Fail: ParseError</b>:
Escaping expressions
In addition to using the math property, you can also quote as a child allowing the use of { } in your expression.
ReactDOM.render(<BlockMath>{"\\frac{\\text{m}}{\\text{s}^2}"}</BlockMath>,
document.getElementById('math'));Or Multiline
ReactDOM.render(<BlockMath>{`\\frac{\\text{m}}
{\\text{s}^2}`}</BlockMath>,
document.getElementById('math'));However, it can be annoying to escape backslashes. This can be circumvented with the String.raw tag on a template literal when using ES6.
ReactDOM.render(<BlockMath>{String.raw`\frac{\text{m}}{\text{s}^2}`}</BlockMath>,
document.getElementById('math'));Backticks must be escaped with a backslash but would be passed to KaTeX as \`. A tag can be created to replace \` with `
const latex = (...a) => String.raw(...a).replace("\\`","`")
ReactDOM.render(<BlockMath>{latex`\``}</BlockMath>,
document.getElementById('math'));You can even do variable substitution
const top = "m";
const bottom = "s";
ReactDOM.render(<BlockMath>{String.raw`\frac{\text{${top}}}{\text{${bottom}}^2}`}</BlockMath>,
document.getElementById('math'));
