String '；“字符串”；不可转换为'；[（字符串）]'；

我试图将URL返回的字符串拆分为“，”，但当我尝试

var tagArray = [String]()
if response.responseObject != nil {
                let data = response.responseObject as NSData
                let str = NSString(data: data, encoding: NSUTF8StringEncoding)!
                self.tagArray = str.componentsSeparatedByString(", ") as String
                println("response: \(self.tagArray)") //prints the HTML of the page
            }

作为字符串的行

self.tagArray=str.componentsSeparatedByString（“，”）抛出错误“'String'不能转换为'[（String）]”

有人知道如何正确地将字符串拆分到数组中吗？
有问题的行缺少强制转换中的
[]
——当您需要强制转换到
字符串数组时，您正在强制转换到
字符串
：

var tagArray = [String]()
if response.responseObject != nil {
    let data = response.responseObject as NSData
    let str = NSString(data: data, encoding: NSUTF8StringEncoding)!
    self.tagArray = str.componentsSeparatedByString(", ") as [String]
    println("response: \(self.tagArray)") //prints the HTML of the page
}