Question

我的json：

function serverValidateQuestion(survey, options) {
            console.log('Validation called');
            console.log(options);
            console.log(options.data.numhousehold);
            console.log(options.data.householdtype);
            console.log(options.data.householdtype.children);

我的JavaScript是：

any

这样我可以访问“ console.log（options.data.householdtype）”，它为我提供了家用类型的项目列表。但是，我试图访问来自familytype的“儿童”值输入。当我编写console.log（options.data.householdtype.children）时，它给我“无法读取未定义的属性”错误

Answer 1

var options = {
"locale": "en",
"title": " Survey",
"focusFirstQuestionAutomatic": false,
"pages": [{
	"name": "livingEnvironment",
	"elements": [{
			"type": "html",
			"name": "navigationWarning",
			"html": "warning"
		},
		{
			"type": "html",
			"name": "IntroEnvironment",
			"html": "We will now ask you questions about your living environment ."
		},
		{
			"type": "text",
			"name": "numhousehold",
			"width": "auto",
			"title": "How many people (including yourself) lived in your household at the time of Hurricane Harvey? ",
			"validators": [{
					"type": "numeric",
					"text": "Please enter a number between 1 and 99.",
					"minValue": 1,
					"maxValue": 99
				},
				{
					"type": "expression",
					"text": "you wrong here",
					"expression": "{numhousehold} > {householdtype.children}"
				}
			],
			"inputType": "number"
		},
		{
			"type": "multipletext",
			"name": "householdtype",
			"width": "auto",
			"title": "Of these, how many (including yourself) were:",
			"items": [{
					"name": "children",
					"inputType": "number",
					"title": "Children under 18 years old",
					"validators": [{
						"type": "regex",
						"text": "One of the numbers below is out of range. Please enter 0, a positive number, or leave the box blank.",
						"regex": "^(\\s*|\\d+)$"
					}]
				},
				{
					"name": "adults",
					"inputType": "number",
					"title": "Adults between 18-59 years old",
					"validators": [{
						"type": "regex",
						"text": "One of the numbers below is out of range. Please enter 0, a positive number, or leave the box blank.",
						"regex": "^(\\s*|\\d+)$"
					}]
				},
				{
					"name": "seniors",
					"inputType": "number",
					"title": "Seniors (60+)",
					"validators": [{
						"type": "regex",
						"text": "One of the numbers below is out of range. Please enter 0, a positive number, or leave the box blank.",
						"regex": "^(\\s*|\\d+)$"
					}]
				}
			]
		}
	]
}]
};
   
   //var options = JSON.parse(str); //don't need if it's already JSON
   console.log('Validation called');       
   console.log(options.pages[0].elements[3].items[0].name); //accesses elements without a loop

//loop through all the nested elements to get the names
for(var page in options.pages) {    
    console.log("Page name: " + options.pages[page].name);         
    for(var element in options.pages[page].elements) {    
        console.log("Element name: " + options.pages[page].elements[element].name);
        for(var item in options.pages[page].elements[element].items) {    
            console.log("Item name: " + options.pages[page].elements[element].items[item].name);
        }    
    }
}

这是我根据您的新问题解答的最新答案：

同样，“子项”位于“项”数组中：“ householdtype”下没有数组。另外，如果您可以控制接收到的json，则将其保留为上面显示的json格式（而不是字符串）有助于使代码更简单，更易于调试，并且您不必使用parse()。

JSON属性无法访问-“无法读取未定义的属性”

1 个答案: