仅在传单弹出窗口中显示填充的属性(而不是"null"属性)

Question

我的传单地图显示了来自GeoJSON文件的多边形。此文件具有多个属性（attribute_1、attribute_2等）。但是，有些是用文本填充的，有些是空的。

如何在我的弹出窗口中只显示填充文本的属性，而不显示空属性？

在每个属性下面显示使用我的代码，如果为空，则弹出窗口中显示"null"：

// Integrate GeoJSON and style polygons
  $.getJSON("klimagutachten_2001.geojson",function(klimagutachten){
    L.geoJson( klimagutachten, {
        style: function(feature){
            return {
                color: "#e60000",
                weight: 4,
                fillColor: "#e60000",
                fillOpacity: .3
            };
        },
// Call popup
        onEachFeature: function( feature, layer ){
            layer.bindPopup("<strong> Attribute 1: "" + feature.properties.attribute_1 + " and the second attribute is: " + feature.properties.attribute_2)
        }                                                                                                       
    }).addTo(map);
  });

Answer 1

创建验证：

onEachFeature: function( feature, layer ){
var text = "";
if (!feature.properties.attribute_1) {
    text += feature.properties.attribute_1 +" "; 
}
if (!feature.properties.attribute_2) {
    text += feature.properties.attribute_2 +" "; 
}
layer.bindPopup(text);
} 

Answer 2

我用一个简单的if解决了这个问题。否则声明。新增内容以粗体突出显示：

// Integrate GeoJSON and style polygons
  $.getJSON("klimagutachten_2001.geojson",function(klimagutachten){
    L.geoJson( klimagutachten, {
        style: function(feature){
            return {
                color: "#e60000",
                weight: 4,
                fillColor: "#e60000",
                fillOpacity: .3
            };
        },
// Call popup
        onEachFeature: function( feature, layer ){
        var attribute_1 = feature.properties.attribute_1;
        if (attribute_1 == null) {
            attribute_1 = "";
        } else {
            var attribute_1 = feature.properties.attribute_1;
        };
            layer.bindPopup("<strong> Attribute 1: "" + attribute_1 + " and the second attribute is: " + feature.properties.attribute_2)
        }   
    }).addTo(map);
  });