在迅速

Question

与NSMutableArray的工作，我有一个字符串的NSMutableArray skippedArray。

skipped Array = ["string1","string2","string3","string4"]; 

我想将索引0处的字符串分配给UILabel。

我试图lblQuestion.text = skippedArray[j] as! String ，但在这条线的应用程序崩溃。

谁能帮助？

Answer 1

定义的NSMutableArray这样的：

let skippedArray = ["string1","string2","string3","string4"]; 
lblQuestion.text = skippedArray.first 

或者您也可能是这样的代码：

let skippedArray : NSMutableArray =   ["string1","string2","string3","string4"]; 
lblQuestion.text = skippedArray.firstObject as! String 

还有另一种方法这样抓取的NSMutableArray的对象：

let skippedArray : NSMutableArray = ["string1","string2","string3","string4"]; 
let j = 0; 
lblQuestion.text = skippedArray.object(at: j) as! String 

Answer 2

定义你的变量数组或干脆[字符串]或只是让定义其定义如下：

var skippedArray: Array<String> = ["string1","string2","string3","string4"] 

或

var skippedArray: [String] = ["string1","string2","string3","string4"] 

或

var skippedArray = ["string1","string2","string3","string4"] 

Answer 3

首先，定义可变数组正确，如

前面提到的

var skippedArray = ["string1","string2","string3","string4"] 

其次，定义您的索引，你称之为 “J” 与您的字符串

let j = 0 

三，设置标签文本，从字符串数组

lblQuestion.text = skippedArray[j]