javascript - 验证JSON数组长度

我正在尝试编写一个if语句，该语句确定getDept JSON数组是否包含多个值。如果是这样，则重定向到另一个页面。通过我的研究，似乎它就像getDept.length > 1一样简单，但是我仍然无法完成这项工作。

我的Javascript代码如下：

$.getJSON("https://apex.oracle.com/pls/apex/mfajertest1/department/"+$x('P2_DEPT_NO').value, function(getDept)
{
    console.log(getDept);
    if(getDept.length == 0)
        {
                window.alert("No Department with that ID");
        }
    else if(getDept.length > 1)
        {
                apex.navigation.redirect('f?p=71293:11');
        }
    else
        {
    $x('P2_DEPT_NAME').readOnly = false;
    $x('P2_DEPT_NAME').value=getDept.items[0].dname;
    $x('P2_DEPT_NAME').readOnly = true;
    $x('P2_DEPT_LOC').readOnly = false;
    $x('P2_DEPT_LOC').value=getDept.items[0].loc;
    $x('P2_DEPT_LOC').readOnly = true;
    $x('P2_DEPT_NO').readOnly = true;
  }
});

getDept JSON数组包含以下信息：

{
    "next": {
        "$ref": "https://apex.oracle.com/pls/apex/mfajertest1/department/%7Bid%7D?page=1"
    },
    "items": [
        {
            "deptno": 10,
            "dname": "accounting",
            "loc": "madison"
        },
        {
            "deptno": 20,
            "dname": "Finance",
            "loc": "Milwaukee"
        },
        {
            "deptno": 30,
            "dname": "IT",
            "loc": "La Crosse"
        },
        {
            "deptno": 40,
            "dname": "Purchasing",
            "loc": "Green Bay"
        },
        {
            "deptno": 10,
            "dname": "Accounting II",
            "loc": "Madison II"
        },
        {
            "deptno": 50,
            "dname": "Sports",
            "loc": "Waukasha"
        }
    ]
}

如果需要，我很乐意提供有关此问题的更多信息。

最佳答案

您的JSON响应实际上是一个对象，而不是数组。您要检查的数组是该对象内名为items的属性。因此，无论您在哪里使用getDept，都应该使用getDept.items：

$.getJSON("https://apex.oracle.com/pls/apex/mfajertest1/department/"+$x('P2_DEPT_NO').value, function(getDept)
{
    console.log(getDept.items);
    if(getDept.items.length == 0)
        {
                window.alert("No Department with that ID");
        }
    else if(getDept.items.length > 1)
        {
                apex.navigation.redirect('f?p=71293:11');
        }
    else
        {
    $x('P2_DEPT_NAME').readOnly = false;
    $x('P2_DEPT_NAME').value=getDept.items[0].dname;
    $x('P2_DEPT_NAME').readOnly = true;
    $x('P2_DEPT_LOC').readOnly = false;
    $x('P2_DEPT_LOC').value=getDept.items[0].loc;
    $x('P2_DEPT_LOC').readOnly = true;
    $x('P2_DEPT_NO').readOnly = true;
  }
});