gatsby / react中多维数组上的map（）方法，尝试在div中包装内部循环时出错 [英] map() method on multi dimensional array in gatsby/react, getting error while trying to wrap inner loop in div

问题描述

我想在gatsbyjs网页中每行显示三个帖子。我有一个帖子数组，如果我要使用列显示，那只会在帖子容器div上应用多行类。但是我使用的是内置于bulma css中的图块布局，不幸的是，它不支持多行赞列。

所以我必须将每三个帖子都包装在div中，类为'tile '。为此，我将数组分为3个大小的块（有人建议在这里，多亏了他），现在归结为遍历二维数组。

现在问题出在我在尝试将内部循环包装到div中时遇到语法错误（我是javascript / es6的新手，而且react / gatsby是我的新手，所以我希望这里有人会帮助我）是下面的代码，我将divs注释为我正在出错。所以如何在gatsby / react中将内部循环包装在div中。 TIA

  return（
< div className = tile is-ancestor> 
 {chunks.map（ （chunk）=> {
 return（
 // // 
 chunk.map（（edge）=> {
 return （
< div className = tile is-parent is-4> 
< div className = {`tile is-child notification $ {edge.node.frontmatter.type}`} > 
< p className = is-7> {edge.node.frontmatter.date}< / p> 
< h2 className =字幕是-5> ; {edge.node.frontmatter.title}< / h2> 
< p> {edge.node.excerpt}< / p> 
< / div> 
< / div> 
）
} 
 ）
 //< / div> 
）
}）} 
< / div> 
）; 
  

解决方案

您需要将代码包装在该div中大括号{}为有效的JSX。就像您对第一个chunks.map所做的一样。

  return（
< div className = tile is-ancestor> 
 {chunks.map（（chunk）=> {
 return（
< div class = tile> 
 {
 chunk.map（（edge）=> {
 return（
< div className = tile is-parent is-4> 
< div className = {`tile is-child notification $ {edge.node.frontmatter.type}`}> 
< p className = is-7> {edge.node.frontmatter.date}< / p> 
< h2 className = subtitle is-5> {edge.node.frontmatter.title}< / h2> 
< p&g t; {edge.node.excerpt}< / p> 
< / div> 
< / div> 
）
} 
）
} 
< / div> 
）
}）} 
< / div> 
）;  

i want to display three posts per row in a gatsbyjs web page. i am having an array of posts, if i were to display using columns it would be just applying the multiline class on the posts container div. but i am using tiles layout built-in in bulma css, unfortunately that don't support multiline likes columns do.

so i have to wrap every three posts in a div with class 'tile'. for which i split the array into chunks of 3 size each (as suggested by someone here, thanks to him) now it boiled down to looping through a two dimensional array.

now the problem is i am getting syntax error when trying to wrap the inner loop in a div (i am new to javascript/es6 and react/gatsby, so i am hoping someone here would help me out) below is the code, i commented out the divs for which i am getting error. so how to wrap the inner loop in a div in gatsby/react. TIA

return(
        <div className="tile is-ancestor">
               {chunks.map((chunk)=> {
                 return (
                   //<div class="tile">
                      chunk.map((edge) => {
                          return(
                            <div className="tile is-parent is-4">
                              <div className={`tile is-child notification ${edge.node.frontmatter.type}`}>
                              <p className="is-7">{edge.node.frontmatter.date}</p>
                              <h2 className="subtitle is-5">{edge.node.frontmatter.title}</h2>
                              <p>{edge.node.excerpt}</p>
                              </div>
                            </div>
                          )
                        }
                      )
                    //</div>
                    )
            })}
        </div>
);

解决方案

You would need to wrap the code inside that div in curly braces { } to be valid JSX. Just like you did with the first chunks.map.

return(
        <div className="tile is-ancestor">
               {chunks.map((chunk)=> {
                 return (
                   <div class="tile">
                    {
                      chunk.map((edge) => {
                          return(
                            <div className="tile is-parent is-4">
                              <div className={`tile is-child notification ${edge.node.frontmatter.type}`}>
                              <p className="is-7">{edge.node.frontmatter.date}</p>
                              <h2 className="subtitle is-5">{edge.node.frontmatter.title}</h2>
                              <p>{edge.node.excerpt}</p>
                              </div>
                            </div>
                          )
                        }
                      )
                     }
                    </div>
                    )
            })}
        </div>
);

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