ios - swift 3，JSON，编写时顶级类型无效
<p><p>我有两个完全正确的 json 对象，一个是从函数创建的，另一个是硬编码的，硬编码的一个有效，另一个无效(它总是提示错误 <code>invalid top-level type</code> ，这很奇怪。任何提示？Tks</p>
<pre><code>let myData = self.dailyMileage?.toDictionary()
let directData = ["orgId" : self.orgId, "driverId" : self.driverId, "date" : Utils.getTodaysDate() ] as
//this won't work unless I substitute myData with directData
let jsonData = try JSONSerialization.data(withJSONObject: myData, options: .prettyPrinted)
//this is the function that produces myData, and nothing is nil
public func toDictionary() -> {
let dict = [ "orgId" : orgId , "driverId": driverId, "date" : date] as
return dict
}
</code></pre></p>
<br><hr><h1><strong>Best Answer-推荐答案</ strong></h1><br>
<p>文档中给出的 <p><code>JSONSerialization</code>:</p>
<blockquote>
<p>An object that may be converted to JSON must have the following properties:</p>
<p>The top level object is an NSArray or NSDictionary. All objects are instances of NSString, NSNumber, NSArray, NSDictionary, or NSNull.</p>
<p>All dictionary keys are instances of NSString. Numbers are not NaN or infinity.</p>
<p>Other rules may apply. Calling isValidJSONObject(_:) or attempting a conversion are the definitive ways to tell if a given object can be converted to JSON data.</p>
</blockquote>
<ol>
<li><p>我认为来自函数的那个可能有一个 NSDate 对象而不是一个 NSString 对象。</p>
</li>
<li><p>另一个原因是因为您的 <code>myData</code> 对象是可选的。 <code>JSONSerialization</code> 可能会出现错误，例如对象是可选的。</p>
</li>
</ol>
<p>请检查是否是由于这两个原因之一。随时提出修改建议以使其变得更好。</p></p>
<p style="font-size: 20px;">关于ios - swift 3，JSON，编写时顶级类型无效，我们在Stack Overflow上找到一个类似的问题：
<a href="https://stackoverflow.com/questions/40453343/" rel="noreferrer noopener nofollow" style="color: red;">
https://stackoverflow.com/questions/40453343/
</a>
</p>
页:
[1]