正如您在下面的代码示例中看到的那样,它是react组件中render()块的一部分,我试图在外部循环中呈现变量“folder”的值。不幸的是,代码部分
<div>{folder}</div>
似乎被忽略了。任何人都可以帮助我找到从外部循环输出当前文件夹值的正确语法?
{
folders.map((folder,_index1) => {
<div>{folder}</div>
return (
items.map((item, index) => {
return (
<div>
{(folder === item.folder) ?
<Draggable
key={item.id}
draggableId={item.id}
index={index}>
{(provided, snapshot) => (
<div
ref={provided.innerRef}
{ ...provided.draggableProps }
{ ...provided.dragHandleProps }
style={getItemStyle(
snapshot.isDragging,
provided.draggableProps.style
)}>
<div>
{item.content}
</div>
</div>
)}
</Draggable>
: null
}
</div>
)})
)})
}
遵循Zydnar上面的评论:
它应该是这样的:
{
folders.map((folder,_index1) => {
return (
<> // or <React.Fragment> with the corresponding closing tag
<div>{folder}</div> // this has to be part of what is returned
items.map((item, index) => {
return (
<div>
{(folder === item.folder) ?
...
</>
)})
)})
}