基于是否有href路径显示/隐藏btn

Question

我有一个json文件是这样的..。

[
  {
    "id": "01",
    "image": "_img/speakers/2019/Abigail L.jpg",
    "organization": "Mumsnet",
    "name": "Abigail Lebrecht",
    "para": "Stopwords personalisation and Text cleaning at Mumsnet",
    "slides": "#"
  },

  {
    "id": "02",
    "image": "_img/speakers/2019/Alexis Iglauer.jpg",
    "organization": "PartnerRe",
    "name": "Alexis Iglauer",
    "para" : "Medical underwriting triage: An end-to-end machine learning case study",
    "slides": "assets/slides/Thurs 12 Sept/Stream 3 session 3/Alexis Iglauer.pptx"
  },

  {
    "id": "03",
    "image": "_img/speakers/2019/Amanda Beedham.jpg",
    "organization": "RSA Insurance",
    "name": "Amanda Beedham",
    "para": "Harnessing AI to Create Insight from Text",
    "slides": "assets/slides/Weds 11 Sept/Stream 3 session 2/AmandaBeedham_RSA.pptx"
  }
]

该文件实际上要大得多，但是有一些id将幻灯片键值设置为#....

我使用JavaScript将一堆HTML注入到如下所示的网页中：

// get json file from directory
fetch("_img/speakers/speakers2019.json")
// store json data in res variable
.then(res => res.json())
// loop through json array and output mark up to target
// in index.html on line 447
.then(speakerArr => {

  var div = document.querySelector('.row_tile');
  for(var i = 0; i < speakerArr.length; i++) {
    div.innerHTML += `<div class="col-lg-3 col-xs-6">
    <div class="hover-element member member-2" data-title-position="center,center">
      <div class="hover-element__initial">
        <img src="${speakerArr[i].image}" />
      </div>
      <div class="hover-element__reveal fade-transiton" data-overlay="9">
        <div class="boxed">
          <h6>${speakerArr[i].organization}</h6>
          <h5>${speakerArr[i].name}</h5>
          <p class="small-text">${speakerArr[i].para}</p>
          <a class="modalbutton" href="${speakerArr.slides}" download>Slides</a>
        </div>
      </div>
    </div>
  </div>`;
  }
});

但是这个循环遍历json并显示json中所有条目的按钮<a class="modalbutton" href="${speakerArr.slides}" download>Slides</a>。我遇到的问题是，并不是所有的按钮都有指向的链接；我如何修改这段代码，这样它就可以在任何地方(键/值是# )都显示ok，不要显示按钮。

到目前为止，我已经尝试过这样做：

  for(var i = 0; i < speakerArr.length; i++) {
    div.innerHTML += `<div class="col-lg-3 col-xs-6">
    <div class="hover-element member member-2" data-title-position="center,center">
      <div class="hover-element__initial">
        <img src="${speakerArr[i].image}" />
      </div>
      <div class="hover-element__reveal fade-transiton" data-overlay="9">
        <div class="boxed">
          <h6>${speakerArr[i].organization}</h6>
          <h5>${speakerArr[i].name}</h5>
          <p class="small-text">${speakerArr[i].para}</p>
          if(speakerArr[i].slides === "#"){
            <a class="modalbutton" href="${speakerArr[i].slides}" download>Slides</a>
          } else {
            <a class="modalbutton disabled" href="${speakerArr[i].slides}" download>Unavailable</a>
          }
        </div>
      </div
    </div>
  </div>`;
  }
});

但是这不像预期的那样工作，我们如何在中获得if/ get

理想情况下，我不想在任何地方显示一个按钮-- json中的键/值是# --这怎么可能呢？

Answer 1

我建议添加另一个具有动态按钮的变量：

var btn = ``;
for (var i = 0; i < speakerArr.length; i++) {

    if (speakerArr[i].slides === "#"){
        btn = `<a class="modalbutton" href="${speakerArr[i].slides}" download>Slides</a>`;
    } else {
        btn = `<a class="modalbutton disabled" href="${speakerArr[i].slides}" download>Unavailable</a>`;
    }

    div.innerHTML += `<div class="col-lg-3 col-xs-6">
    <div class="hover-element member member-2" data-title-position="center,center">
      <div class="hover-element__initial">
        <img src="${speakerArr[i].image}" />
      </div>
      <div class="hover-element__reveal fade-transiton" data-overlay="9">
        <div class="boxed">
          <h6>${speakerArr[i].organization}</h6>
          <h5>${speakerArr[i].name}</h5>
          <p class="small-text">${speakerArr[i].para}</p>
          ${btn}
        </div>
      </div>
    </div>
  </div>`;
}

更新：，扩展@Bek的答案，下面是如何使用三元操作符

for (var i = 0; i < speakerArr.length; i++) {
    div.innerHTML += `<div class="col-lg-3 col-xs-6">
    <div class="hover-element member member-2" data-title-position="center,center">
      <div class="hover-element__initial">
        <img src="${speakerArr[i].image}" />
      </div>
      <div class="hover-element__reveal fade-transiton" data-overlay="9">
        <div class="boxed">
          <h6>${speakerArr[i].organization}</h6>
          <h5>${speakerArr[i].name}</h5>
          <p class="small-text">${speakerArr[i].para}</p>
          ${speakerArr[i].slides == '#' ? `<a class="modalbutton" href="${speakerArr[i].slides}" download>Slides</a>` : `<a class="modalbutton disabled" href="${speakerArr[i].slides}" download>Unavailable</a>`}
        </div>
      </div>
    </div>
  </div>`;
}

Answer 2

在您的情况下，这应该是可行的：

 for(var i = 0; i < speakerArr.length; i++) {
    div.innerHTML += `<div class="col-lg-3 col-xs-6">
    <div class="hover-element member member-2" data-title-position="center,center">
      <div class="hover-element__initial">
        <img src="${speakerArr[i].image}" />
      </div>
      <div class="hover-element__reveal fade-transiton" data-overlay="9">
        <div class="boxed">
          <h6>${speakerArr[i].organization}</h6>
          <h5>${speakerArr[i].name}</h5>
          <p class="small-text">${speakerArr[i].para}</p>`;
          if(speakerArr[i].slides !== "#"){
            div.innerHTML += `<a class="modalbutton" href="${speakerArr[i].slides}" download>Slides</a>`;
          } 
        div.innerHTML += `</div>
      </div>
    </div>
  </div>`;
  }

Answer 3

尝试使用这样的三元运算符：

`${speakerArr[i].slides == '#' ? '<a class="modalbutton" href="${speakerArr[i].slides}" download>Slides</a>' : '<a class="modalbutton disabled" href="${speakerArr[i].slides}" download>Unavailable</a>'}`