在 javascript 代码中简化类似的对象文字

Question

有什么方法可以简化这段代码，我很感激任何想法。在 lyerDefs 中，我对从 1 到 11 的所有对象具有相同的值。

spider = L.esri.dynamicMapLayer({
    url:API,
    layers:[1,2,3,4,5,6,7,8,9,10,11],
    layerDefs:{ // how to simplify following code?

      1:  "Site_id ='"+ activeSiteId +"'",
      2:  "Site_id ='" + activeSiteId +"'",
      3:  "Site_id ='"+ activeSiteId +"'",
      4:  "Site_id ='"+ activeSiteId +"'",
      5:  "Site_id ='"+ activeSiteId +"'",
      6:  "Site_id ='"+ activeSiteId +"'",
      7:  "Site_id ='"+ activeSiteId +"'",
      8:  "Site_id ='"+ activeSiteId +"'",
      9:  "Site_id ='"+ activeSiteId +"'",
      10:  "Site_id ='"+ activeSiteId +"'",
      11:  "Site_id ='"+ activeSiteId +"'"

    }
  } );

Answer 1

这取决于你简化它的意思。我假设您不想重复 "Site_id = '" + activeSiteId +"'" 字符串 11 次。如果仅此而已，那么应该这样做：

var layers = [];
var layerDefs = {};
for(i = 1; i < 12; i++) {
  layers.push(i);
  layerDefs[i] = "Site_id = '" + activeSiteId + "'";
}
spider = L.esri.dynamicMapLayer({
  url:API,
  layers: layers,
  layerDefs: layerDefs
});

Answer 2

您可以创建一个函数来生成图层和 layerDef。下面的示例使用 .reduce 方法。

function generateLayersAndDefs(layers) {
  return {
    layers: layers,
    layerDefs: layers.reduce(function(final, current) {
      final[current] = "Site_id ='" + current + "'"
      return final;
    }, {})
  };
}

spider = L.esri.dynamicMapLayer(
  Object.assign(
    {
      url:API
    },
    generateLayersAndDefs([1,2,3,4,5,6,7,8,9,10,11])
  )
);

在 javascript 代码中简化类似的对象文字

Simplify similar Object Literal in javascript code

javascript

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esri