Question

我正在使用以下函数检索一些JSON数据。单击一个元素并使用数据创建表格，使用图像填充单元格并将表格附加到div时调用它。

function LoadImagesByCategory() {
    $.getJSON("/Service/GetJson.ashx?data=images", function(data) {
        jsObjectData = data.ImageCollection.Images;
        //Create a table named imageTable
        $("#imagesByCategory").append(imageTable);
        }
    })

jsObjectData看起来像这样。

{"ImageCollection":
    {"Images":
    [{  "ImageID":"68",
        "CatID":"1",
        "Name":"uploadedFile",
        "Location":"/Images/Art/Full/68.gif",
        "ClipLocation":"/Images/Art/Clips/68.gif",
        "FullHeight":"504",
        "FullWidth":"451"
       },
       { "ImageID":"69",
         "CatID":"1",
         "Name":"uploadedFile",
         "Location":"/Images/Art/Full/69.gif",
         "ClipLocation":"/Images/Art/Clips/69.gif",
         "FullHeight":"364",
         "FullWidth":"500"
        },
        etc. etc 
     ]
   }
 }

它包含有关FullHeight和FullWidth等图像的其他信息，我希望能够在单击img时检索这些图像。例如，如果我将img的id设置为“68ArtImage”，其中68是ImageID，我希望能够将68传递给附加到jsObjectData的函数并检索相应的图像数据。问题首先是我不知道如何使对象有用。在函数外面，第二个我不知道如何将函数附加到对象。

Answer 1

再次阅读你的问题后，也许这就是你想要的？

function getImageData(id, json){
    for(i in json.ImageCollection.Images){
       if( json.ImageCollection.Images[i].ImageID == 69){
            return json.ImageCollection.Images[i];
       }
    }
    return false;
}

getImageData将搜索给定的json对象并返回图像对象（如关联数组），否则为false。

示例：

var json = {"ImageCollection":
    {"Images":
    [{  "ImageID":"68",
        "CatID":"1",
        "Name":"uploadedFile",
        "Location":"/Images/Art/Full/68.gif",
        "ClipLocation":"/Images/Art/Clips/68.gif",
        "FullHeight":"504",
        "FullWidth":"451"
       },
       { "ImageID":"69",
         "CatID":"1",
         "Name":"uploadedFile",
         "Location":"/Images/Art/Full/69.gif",
         "ClipLocation":"/Images/Art/Clips/69.gif",
         "FullHeight":"364",
         "FullWidth":"500"
        }
     ]
   }
 }

function getImageData(id, json){
    for(i in json.ImageCollection.Images){
       if( json.ImageCollection.Images[i].ImageID == 69){
            return json.ImageCollection.Images[i];
       }
    }
    return false;
}

if(image = getImageData(69, json)){
    alert('found the image wooo!');
    // now do something with your image object
}
else{
    alert('no image with that id found');
}

Answer 2

这是一些伪代码：

//global
var gImageTable = {};


function LoadImagesByCategory() {
  $.getJSON("/Service/GetJson.ashx?data=images", function(data) {
    jsObjectData = data.ImageCollection.Images;
    // Add the images to the image table
    for (var i=0; i < jsObjectData.length; i++) {
      var img = jsObjectData[i];
      gImageTable[img.ImageId] = img;
    }

    // Create a table named imageTable. Should add the id into each of the images
    // so we can access its data from the click handler
    $("#imagesByCategory").append(imageTable);
  })
}

// The click handler that knows about image map structure
$("#imagesByCategory").click(function (e) {
  // or something smarter to detect that it
  // was a click within one of the images
  if (e.target.tagName == "IMG") {
    var imageData = gImageTable[e.target.id];    
    console.log(imageData.CatID, imageData.FullHeight);
  }
});

这不是我将它投入生产的方式。我讨厌全局变量，所以我会有一个管理该表的对象。然后该对象可以保存对imageTable的引用

如何在函数外部使Javascript对象可用？

2 个答案: