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Reactjs React return中的条件语句导致语法错误_Reactjs - Fatal编程技术网

Reactjs React return中的条件语句导致语法错误

Reactjs React return中的条件语句导致语法错误,reactjs,Reactjs,我在返回中遇到语法问题。我正在尝试检查数组项是否存在。问题是我如何编写我认为的代码 导致错误的代码是: { nodes.childItems ? "has child" : "no child" } Syntax error: Unexpected token, expected "," 错误是: { nodes.childItems ? "has child" : "no child"

我在返回中遇到语法问题。我正在尝试检查数组项是否存在。问题是我如何编写我认为的代码

导致错误的代码是:

{ nodes.childItems ? "has child"  : "no child" } 
Syntax error: Unexpected token, expected ","
错误是:

{ nodes.childItems ? "has child"  : "no child" } 
Syntax error: Unexpected token, expected ","
我该如何在报税表中填写此信息

  const MyNav = () => {
  const [allNavItems, setAllNavItems] = useState(null);

  useEffect(() => {
    const run = async () => {
      const items = await getNavMenu();
      
      setAllNavItems(items);
    };

    run();
  }, []);

  if (!allNavItems) return null;

  return (
    <Navbar bg="light" expand="lg">
      <Navbar.Brand href="#home">React-Bootstrap</Navbar.Brand>
      <Navbar.Toggle aria-controls="basic-navbar-nav" />
      <Navbar.Collapse id="basic-navbar-nav">
        <Nav className="mr-auto">
          <Nav.Link href="/">Home</Nav.Link>
            {allNavItems.menuItems && allNavItems.menuItems.nodes.map((nodes) => (
              <Nav.Link href={nodes.path}>{nodes.label}, {nodes.parentId}, {nodes.id} </Nav.Link>
              { nodes.childItems ? "has child"  : "no child "   } 
            ))}
          </Nav>
        </Navbar.Collapse>
      </Navbar>
    )
  }
constmynav=()=>{
常量[allNavItems,setAllNavItems]=useState(null);
useffect(()=>{
const run=async()=>{
const items=等待getNavMenu();
设置所有导航项(项目);
};
run();
}, []);
如果(!allNavItems)返回null;
返回(
反应自举
家
{allNavItems.menuItems&&allNavItems.menuItems.nodes.map((nodes)=>(
{nodes.label},{nodes.parentId},{nodes.id}
{nodes.childItems?“有子项”:“无子项”}
))}
)
}

在JSX中,您需要包含一个主元素,因此将其更改为:

<>
   <Nav.Link href={nodes.path}>    {nodes.label}, {nodes.parentId}, {nodes.id} </Nav.Link>
   { nodes.childItems   ? "has child"  : "no child "   } 
</>

{nodes.label},{nodes.parentId},{nodes.id}
{nodes.childItems?“有子项”:“无子项”}