React Array.map not populating table [duplicate] - javascript

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List elements not rendering in React [duplicate]
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I have a react component that is supposed to take an array of items passed to the component as a prop and render a table. I have done this successfully with another component already. Yet for some reason, the table does not want to populate rows in this component.
Here is the component that renders the :
class OrderList extends React.Component {
constructor(props) {
super(props);
this.populateTable = this.populateTable.bind(this);
}
populateTable() {
return this.props.orders.map((order) => {
<tr key={order.id}>
<td>{order.orderNo}</td>
<td>{order.customer.name}</td>
<td>{order.customerPO}</td>
<td>{order.orderDate}</td>
<td>{order.shipDate}</td>
</tr>
});
}
render() {
return(
<Table striped bordered hover>
<thead>
<tr>
<td>Order No.</td>
<td>Customer Name</td>
<td>Customer P.O.</td>
<td>Order Date</td>
<td>Ship Date</td>
</tr>
</thead>
<tbody>
{this.populateTable()}
</tbody>
</Table>
);
}
}
Using react dev tools, I can see that the orders prop does contain the correct data, and array of objects. I can even throw in a console.log line within the forEach loop, so I know the component is actually looping over the data. However, no rows are rendered?

Your map is not returning anything this is the reason
class OrderList extends React.Component {
constructor(props) {
super(props);
this.populateTable = this.populateTable.bind(this);
}
populateTable() {
return this.props.orders.map((order) => (
<tr key={order.id}>
<td>{order.orderNo}</td>
<td>{order.customer.name}</td>
<td>{order.customerPO}</td>
<td>{order.orderDate}</td>
<td>{order.shipDate}</td>
</tr>
));
}
render() {
return(
<Table striped bordered hover>
<thead>
<tr>
<td>Order No.</td>
<td>Customer Name</td>
<td>Customer P.O.</td>
<td>Order Date</td>
<td>Ship Date</td>
</tr>
</thead>
<tbody>
{this.populateTable()}
</tbody>
</Table>
);
}
}
when you use curly braces in map you have to use return keyword to return anything
in order to return from your method you can try something like this
populateTable() {
return this.props.orders.map((order) => {
return (<tr key={order.id}>
<td>{order.orderNo}</td>
<td>{order.customer.name}</td>
<td>{order.customerPO}</td>
<td>{order.orderDate}</td>
<td>{order.shipDate}</td>
</tr>)
});
}

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import React from "react";
import "./Table.css";
export default function Table({theadData, tbodyData}) {
return (
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There are several mistakes you made:
change forEach to map
replace {} with (), or add return before <tr>
put key on the root element which is <tr>
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You are passing the index i, not the right way. Also i would prefer to pass id rather than index. Here is how you can do that:
import React from 'react';
import { render } from 'react-dom';
class CommentList extends React.Component {
constructor(props) {
super(props);
this.state = {
comments: []
};
this.handleCommentDelete = this.handleCommentDelete.bind(this);
}
handleCommentDelete(id) {
let comments = this.state.comments.filter(comment => comment.id !== id);
this.setState({
comments: comments
});
}
render() {
return (
<table className="commentList">
<thead>
<tr>
<th>Name</th>
<th>Phone</th>
<th>Email</th>
<th></th>
</tr>
</thead>
<tbody>
{
this.props.data.map(comment => {
return (
<tr className="comment" key={comment.Id}>
<td className="commentId">{comment.Id}</td>
<td className="commentName">{comment.Name}</td>
<td className="commentPhone">{comment.Phone}</td>
<td className="commentEmail">{comment.Email}</td>
<td className="commentCRUD">
<a onClick={() => this.handleCommentDelete(comment.Id)}>
<i className="fa fa-trash" />
</a>
</td>
</tr>
);
})
}
</tbody>
</table>
);
}
}
export default CommentList;
Hope this works for you.

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