Here's the basics of how I would go about it. Use classes with properties instead of raw data objects. Create properties for the calculated fields of a person. Pass the objects to React components that know how to display the fields of the Person nicely. A Table component can create a Row for each person, for example.
<!-- begin snippet: js hide: false console: true babel: true -->
<!-- language: lang-js -->
class Person {
constructor({...properties}) {
Object.assign(this, properties);
}
get pf() {
return this.days * 12 / 100;
}
get esi() {
return this.pf * 0.25;
}
get amtPayable() {
return this.pf + this.esi + 100;
}
}
let MyRow = (props) => (
<tr>
<td>{props.item.name}</td>
<td>{props.item.days}</td>
<td>{props.item.pf}</td>
<td>{props.item.esi}</td>
<td>{props.item.amtPayable}</td>
</tr>
);
let MyTable = (props) => (
<table>
<tr>
<th>Name</th>
<th>Days</th>
<th>pf</th>
<th>esi</th>
<th>amtPayable</th>
</tr>
{props.data.map(item => <MyRow item={item} />)}
</table>
);
const data = [
new Person({
key: '1',
name: 'Jerry gold',
days: 101
}),
new Person({
key: '2',
name: 'Arnold Smith',
days: 102
}),
new Person({
key: '3',
name: 'Baker',
days: 103
})
];
// Render it
ReactDOM.render(
<MyTable data={data}>hello</MyTable>,
document.getElementById("react")
);
<!-- language: lang-css -->
table {
border-collapse: collapse;
}
table, th, td {
border: 1px solid black;
padding: 5px;
}
<!-- language: lang-html -->
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/16.6.3/umd/react.production.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react-dom/16.6.3/umd/react-dom.production.min.js"></script>
<div id="react"></div>
<!-- end snippet -->
That's *property spread notation*. It was added in ES2018, but long-supported in React projects via transpilation (as "JSX spread attributes" even though you could do it elsewhere, too, not just attributes).
`{...this.props}` *spreads out* the "own" properties in `props` as discrete properties on the `Modal` element you're creating. For instance, if `this.props` contained `a: 1` and `b: 2`, then
<Modal {...this.props} title='Modal heading' animation={false}>
would be the same as
<Modal a={this.props.a} b={this.props.b} title='Modal heading' animation={false}>
But it's dynamic, so whatever "own" properties are in `props` are included.
Since `children` is an "own" property in `props`, spread will include it. So if the component where this appears had child elements, they'll be passed on to `Modal`. Putting child elements between the opening tag and closing tags is just syntactic sugar — the good kind — for putting a `children` property in the opening tag. Example:
<!-- begin snippet: js hide: true console: true babel: true -->
<!-- language: lang-js -->
class Example extends React.Component {
render() {
const { className, children } = this.props;
return (
<div className={className}>
{children}
</div>
);
}
}
ReactDOM.render(
[
<Example className="first">
<span>Child in first</span>
</Example>,
<Example className="second" children={<span>Child in second</span>} />
],
document.getElementById("root")
);
<!-- language: lang-css -->
.first {
color: green;
}
.second {
color: blue;
}
<!-- language: lang-html -->
<div id="root"></div>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/16.6.3/umd/react.production.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react-dom/16.6.3/umd/react-dom.production.min.js"></script>
<!-- end snippet -->
Spread notation is handy not only for that use case, but for creating a new object with most (or all) of the properties of an existing object — which comes up a lot when you're updating state, since you can't modify state directly:
this.setState(prevState => {
return {foo: {...prevState.foo, a: "updated"}};
});
That replaces `this.state.foo` with a new object with all the same properties as `foo` except the `a` property, which becomes `"updated"`:
<!-- begin snippet: js hide: true console: true babel: false -->
<!-- language: lang-js -->
const obj = {
foo: {
a: 1,
b: 2,
c: 3
}
};
console.log("original", obj.foo);
// Creates a NEW object and assigns it to `obj.foo`
obj.foo = {...obj.foo, a: "updated"};
console.log("updated", obj.foo);
<!-- language: lang-css -->
.as-console-wrapper {
max-height: 100% !important;
}
<!-- end snippet -->
[1]: https://reactjs.org/docs/jsx-in-depth.html#children-in-jsx
