加载后访问jquery json数据？

Question

如何从getJSON命令外部访问我的数据？

//LOAD JSON
$.getJSON("users.js", function(data) {
   numberOfPieces = data.users.length;
   alert("Loaded "+numberOfPieces); //   <------WORKS
});

//Select a piece
var pieceSelected = Math.floor(Math.random() * (numberOfPieces));
alert("pieceSelected: "+data.users[pieceSelected].Name); //   <------RETURNS "data is not defined"

谢谢！

Answer 1

您的问题是函数参数的作用域是该函数，并且在函数外部不可访问。通过使用范围之外的变量，事情应该按预期工作。

var piecesData;

//LOAD JSON
$.getJSON("users.js", function(data) {
   piecesData = data;
   numberOfPieces = data.users.length;
   alert("Loaded "+numberOfPieces); //   <------WORKS
});

//Select a piece
var pieceSelected = Math.floor(Math.random() * (numberOfPieces));
alert("pieceSelected: "+ piecesData.users[pieceSelected].Name);