JSON serialization with Swift 3 - json

Question

I am trying to to populate a table by filling an array from JSON data. I am using the code below but keep getting the error:
Type 'Any' has no subscript members
on the following lines of code:
self.tableData.append(jsonResult[i]["title"]! as! String)
self.tableImages.append(jsonResult[i]["image"]! as! String)
self.tableDesc.append(jsonResult[i]["description"]! as! String)
self.tableValidity.append(jsonResult[i]["validity"]! as! String)
My code:
let str3 = Int(str2!)!
let url = NSURL(string: "https://www.*****.php")!
let task = URLSession.shared.dataTask(with: url as URL) { (data, response, error) -> Void in
if let urlContent = data {
do {
let jsonResult = try JSONSerialization.jsonObject(with: urlContent, options: JSONSerialization.ReadingOptions.mutableContainers)
print(str3)
var i = 0
while i < str3 {
print(jsonResult[i]["title"]! as!String)
print(jsonResult[i]["image"]! as! String)
self.tableData.append(jsonResult[i]["title"]! as! String)
self.tableImages.append(jsonResult[i]["image"]! as! String)
self.tableDesc.append(jsonResult[i]["description"]! as! String)
self.tableValidity.append(jsonResult[i]["validity"]! as! String)
i = i + 1
}
} catch {
print("JSON serialization failed")
}
} else {
print("ERROR FOUND HERE")
}
DispatchQueue.main.async(execute: { () -> Void in
self.tableView.reloadData()
})
}
task.resume()

Answer 1

The compiler doesn't know the type of jsonResult, you have to tell what it is, for example with optional binding like this:
if let jsonResult = try JSONSerialization.jsonObject(with: urlContent, options: []) as? [[String:AnyObject]] {
}
Here I downcast the JSON as an array of dictionaries. Use your loop inside this if let and it should work.

Answer 2

The compiler doesn't know the type the JSON object, you need to cast it to the actual type
let jsonResult = try JSONSerialization.jsonObject(with: urlContent, options:[]) as! [[String:Any]]
Mutable containers are not needed at all.
The C-while loop with incrementing a counter is very ugly. Don't use that in Swift. And you are using too many exclamation marks
for item in jsonResult {
print(item["title"] as! String)
print(item["image"] as! String)
self.tableData.append(item["title"] as! String)
self.tableImages.append(item["image"] as! String)
self.tableDesc.append(item["description"] as! String)
self.tableValidity.append(item["validity"] as! String)
}
PS: And multiple arrays as data source is also clumsy and error-prone. In an object oriented language a custom struct or class is preferable