blocks|key|110755|text|你必须给这本字典一个类型。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|110756|//+empty+dict+with+Ints+as+keys+and+Strings+as+values
var+namesOfIntegers+=+Dictionary<Int,+String>()|code-block|syntax|javascript|110757|如果编译器可以推断类型，则可以使用较短的语法|110758|namesOfIntegers[16]+=+"sixteen"
//+namesOfIntegers+now+contains+1+key-value+pair
namesOfIntegers+=+[:]
//+namesOfIntegers+is+once+again+an+empty+dictionary+of+type+Int,+String|110759|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|N|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|O|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

You have to give the dictionary a type

<pre><code>// empty dict with Ints as keys and Strings as values
var namesOfIntegers = Dictionary&lt;Int, String&gt;()
</code></pre>

If the compiler can infer the type, you can use the shorter syntax

<pre><code>namesOfIntegers[16] = "sixteen"
// namesOfIntegers now contains 1 key-value pair
namesOfIntegers = [:]
// namesOfIntegers is once again an empty dictionary of type Int, String
</code></pre>

blocks|key|110787|text|除非类型信息可用，否则不能使用[:]。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|110788|在这种情况下，您需要显式地提供它：|110789|var+dict+=+Dictionary<String,+String>()|code-block|syntax|javascript|110790|var意味着它是可变的，所以您可以向它添加条目。相反，如果您将其设置为常量，则不能对其进行进一步修改(let表示let+)。|110791|例如，如果可以推断出类型信息，则可以使用[:]速记符号|110792|var+dict+=+["key":+"value"]

//+stuff

dict+=+[:]+//+ok,+I'm+done+with+it|110793|在最后一个示例中，已知字典的第一行有一个Dictionary<String,+String>类型。注意，您不必显式地指定它，但它已经被推断出来了。|110794|entityMap^0|F|3|0|0|0|0|3|1F|3|1K|3|0|K|3|0|0|K|Q|0^^$0|@$1|2|3|4|5|6|7|W|8|@$9|X|A|Y|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|Z|8|@]|D|@]|E|$]]|$1|H|3|I|5|J|7|10|8|@]|D|@]|E|$K|L]]|$1|M|3|N|5|6|7|11|8|@$9|12|A|13|B|C]|$9|14|A|15|B|C]|$9|16|A|17|B|C]]|D|@]|E|$]]|$1|O|3|P|5|6|7|18|8|@$9|19|A|1A|B|C]]|D|@]|E|$]]|$1|Q|3|R|5|J|7|1B|8|@]|D|@]|E|$K|L]]|$1|S|3|T|5|6|7|1C|8|@$9|1D|A|1E|B|C]]|D|@]|E|$]]|$1|U|3|-4|5|6|7|1F|8|@]|D|@]|E|$]]]|V|$]]

You can't use <code>[:]</code> unless type information is available.

You need to provide it explicitly in this case:

<pre><code>var dict = Dictionary&lt;String, String&gt;()
</code></pre>

<code>var</code> means it's mutable, so you can add entries to it.
Conversely, if you make it a <code>let</code> then you cannot further modify it (<code>let</code> means constant).

You can use the <code>[:]</code> shorthand notation if the type information can be inferred, for instance

<pre><code>var dict = ["key": "value"]

// stuff

dict = [:] // ok, I'm done with it
</code></pre>

In the last example the dictionary is known to have a type <code>Dictionary&lt;String, String&gt;</code> by the first line. Note that you didn't have to specify it explicitly, but it has been inferred.

blocks|key|110914|text|我也在玩这个。你可以只声明一个空字典，然后像这样添加一个键/值对，这似乎很奇怪：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|110915|var+emptyDictionary+=+Dictionary<String,+Float>()
var+flexDictionary+=+[:]
emptyDictionary["brian"]+=+4.5
flexDictionary["key"]+=+"value"+//+ERROR+:+cannot+assign+to+the+result+of+this+expression|code-block|syntax|javascript|110916|但是您可以通过使用"Any“类型创建一个接受不同值类型的字典，如下所示：|110917|var+emptyDictionary+=+Dictionary<String,+Any>()
emptyDictionary["brian"]+=+4.5
emptyDictionary["mike"]+=+"hello"|110918|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|N|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|O|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

I'm playing with this too. It seems strange that you can just declare an empty dictionary and then add a key/value pair to it like so :

<pre><code>var emptyDictionary = Dictionary&lt;String, Float&gt;()
var flexDictionary = [:]
emptyDictionary["brian"] = 4.5
flexDictionary["key"] = "value" // ERROR : cannot assign to the result of this expression
</code></pre>

But you can create a Dictionary that accepts different value types by using the "Any" type like so :

<pre><code>var emptyDictionary = Dictionary&lt;String, Any&gt;()
emptyDictionary["brian"] = 4.5
emptyDictionary["mike"] = "hello"
</code></pre>

blocks|key|4617099|text|您可以像这样简单地声明它：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4617100|var+emptyDict:NSMutableDictionary+=+[:]|code-block|syntax|javascript|4617101|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

You can simply declare it like this:

<pre><code>var emptyDict:NSMutableDictionary = [:]
</code></pre>

blocks|key|110962|text|使用这个将会起作用。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|110963|var+emptyDict+=+[String:+String]()|code-block|syntax|javascript|110964|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

Use this will work.

<pre><code>var emptyDict = [String: String]()
</code></pre>

blocks|key|4617159|text|这对你找路很方便。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4617160|var+dict:字典=|4617161|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|F|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|G|8|@]|9|@]|A|$]]|$1|D|3|-4|5|6|7|H|8|@]|9|@]|A|$]]]|E|$]]

It is very handy for finding your way

var dict:Dictionary = [:]

blocks|key|4617185|text|var+dictList+=+String+:+swift中的字典字符串var+arrSectionTitle+=+swift中的数组字符串|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4617186|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

var dictList = String:String for dictionary in swift
 var arrSectionTitle = String for array in swift

blocks|key|4617238|text|Swift+documentation建议使用以下方式初始化空字典：|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|4617239|var+emptyDict+=+[String:+String]()|code-block|syntax|javascript|4617240|当我第一次遇到这个问题时，我有点困惑，因为不同的答案显示了初始化空字典的不同方法。事实证明，实际上有很多方法可以做到这一点，尽管考虑到Swift推断类型的能力，有些方法有点多余或过于冗长。|4617241|var+emptyDict+=+[String:+String]()
var+emptyDict+=+Dictionary<String,+String>()
var+emptyDict:+[String:+String]+=+[:]
var+emptyDict:+[String:+String]+=+[String:+String]()
var+emptyDict:+[String:+String]+=+Dictionary<String,+String>()
var+emptyDict:+Dictionary+=+[String:+String]()
var+emptyDict:+Dictionary+=+Dictionary<String,+String>()
var+emptyDict:+Dictionary<String,+String>+=+[:]
var+emptyDict:+Dictionary<String,+String>+=+[String:+String]()
var+emptyDict:+Dictionary<String,+String>+=+Dictionary<String,+String>()|4617242|在您拥有一个空字典之后，您可以添加一个键值对，如下所示：|4617243|emptyDict["some+key"]+=+"some+value"|4617244|如果要再次清空字典，可以执行以下操作：|4617245|emptyDict+=+[:]|4617246|类型仍然是<String,+String>，因为它是这样初始化的。|style|CODE|4617247|entityMap|0|LINK|mutability|MUTABLE|url|https://developer.apple.com/library/prerelease/ios/documentation/Swift/Conceptual/Swift_Programming_Language/CollectionTypes.html^0|0|J|0|0|0|0|0|0|0|0|0|5|G|0^^$0|@$1|2|3|4|5|6|7|16|8|@]|9|@$A|17|B|18|1|19]]|C|$]]|$1|D|3|E|5|F|7|1A|8|@]|9|@]|C|$G|H]]|$1|I|3|J|5|6|7|1B|8|@]|9|@]|C|$]]|$1|K|3|L|5|F|7|1C|8|@]|9|@]|C|$G|H]]|$1|M|3|N|5|6|7|1D|8|@]|9|@]|C|$]]|$1|O|3|P|5|F|7|1E|8|@]|9|@]|C|$G|H]]|$1|Q|3|R|5|6|7|1F|8|@]|9|@]|C|$]]|$1|S|3|T|5|F|7|1G|8|@]|9|@]|C|$G|H]]|$1|U|3|V|5|6|7|1H|8|@$A|1I|B|1J|W|X]]|9|@]|C|$]]|$1|Y|3|-4|5|6|7|1K|8|@]|9|@]|C|$]]]|Z|$10|$5|11|12|13|C|$14|15]]]]

The <a href="https://developer.apple.com/library/prerelease/ios/documentation/Swift/Conceptual/Swift_Programming_Language/CollectionTypes.html">Swift documentation</a> recommends the following way to initialize an empty Dictionary:

<pre><code>var emptyDict = [String: String]()
</code></pre>

I was a little confused when I first came across this question because different answers showed different ways to initialize an empty Dictionary. It turns out that there are actually a lot of ways you can do it, though some are a little redundant or overly verbose given Swift's ability to infer the type. 

<pre><code>var emptyDict = [String: String]()
var emptyDict = Dictionary&lt;String, String&gt;()
var emptyDict: [String: String] = [:]
var emptyDict: [String: String] = [String: String]()
var emptyDict: [String: String] = Dictionary&lt;String, String&gt;()
var emptyDict: Dictionary = [String: String]()
var emptyDict: Dictionary = Dictionary&lt;String, String&gt;()
var emptyDict: Dictionary&lt;String, String&gt; = [:]
var emptyDict: Dictionary&lt;String, String&gt; = [String: String]()
var emptyDict: Dictionary&lt;String, String&gt; = Dictionary&lt;String, String&gt;()
</code></pre>

After you have an empty Dictionary you can add a key-value pair like this:

<pre><code>emptyDict["some key"] = "some value"
</code></pre>

If you want to empty your dictionary again, you can do the following:

<pre><code>emptyDict = [:]
</code></pre>

The types are still <code>&lt;String, String&gt;</code> because that is how it was initialized.

blocks|key|111173|text|您可以使用以下代码将其声明为nil：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|111174|var+assoc+:+[String:String]|code-block|syntax|javascript|111175|好的是你已经排版了(注意我用的是var和not+let，把它们看作是可变的和不可变的)。然后，您可以稍后填充它：|111176|assoc+=+["key1"+:+"things",+"key2"+:+"stuff"]|111177|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|N|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|O|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

You can declare it as nil with the following:

<pre><code>var assoc : [String:String]
</code></pre>

Then nice thing is you've already typeset (notice I used var and not let, think of these as mutable and immutable). Then you can fill it later:

<pre><code>assoc = ["key1" : "things", "key2" : "stuff"]
</code></pre>

blocks|key|111205|text|var+parking+=+[Dictionary+<+String,+Double+>()]|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|111206|%5E这将为字符串添加一个字典:双输入|unstyled|111207|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$B|C]]|$1|D|3|E|5|F|7|J|8|@]|9|@]|A|$]]|$1|G|3|-4|5|F|7|K|8|@]|9|@]|A|$]]]|H|$]]

<pre><code>var parking = [Dictionary &lt; String, Double &gt;()]
</code></pre>

^ this adds a dictionary for a [string:double] input

blocks|key|111214|text|如果要创建具有任何类型的通用字典|type|unstyled|depth|inlineStyleRanges|entityRanges|data|111215|var+dictionaryData+=+[AnyHashable:Any]()|code-block|syntax|javascript|111216|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

If you want to create a generic dictionary with any type

<pre><code>var dictionaryData = [AnyHashable:Any]()
</code></pre>

blocks|key|111238|text|我通常会用|type|unstyled|depth|inlineStyleRanges|entityRanges|data|111239|var+dictionary:[String:String]+=+[:]
dictionary.removeAll()|code-block|syntax|javascript|111240|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

I'm usually using 

<pre><code>var dictionary:[String:String] = [:]
dictionary.removeAll()
</code></pre>

blocks|key|4617370|text|Swift+4|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4617371|let+dicc+=+NSDictionary()

//MARK:+-+This+is+empty+dictionary
let+dic+=+["":""]

//MARK:-+This+is+variable+dic+means+if+you+want+to+put+variable+
let+dic2+=+["":"",+"":"",+"":""]

//MARK:-+Variable+example
let+dic3+=+["name":"Shakeel+Ahmed",+"imageurl":"https://abc?abc.abc/etc",+"address":"Rawalpindi+Pakistan"]

//MARK:+-+This+is+2nd+Variable+Example+dictionary
let+dic4+=+["name":+variablename,+"city":+variablecity,+"zip":+variablezip]

//MARK:-+Dictionary+String+with+Any+Object
var+dic5a+=+[String:+String]()
//MARK:-+Put+values+in+dic
var+dic5a+=+["key1":+"value",+"key2":"value2",+"key3":"value3"]

var+dic5b+=+[String:AnyObject]()
dic5b+=+["name":+fullname,+"imageurl":+imgurl,+"language":+imgurl]+as+[String+:+AnyObject]

or
//MARK:-+Dictionary+String+with+Any+Object
let+dic5+=+["name":+fullname,+"imageurl":+imgurl,+"language":+imgurl]+as+[String+:+AnyObject]

//MARK:-+More+Easy+Way
let+dic6a+=+NSDictionary()
let+dic6b+=+NSMutalbeDictionary()|code-block|syntax|javascript|4617372|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

Swift 4 

<pre><code>let dicc = NSDictionary()

//MARK: - This is empty dictionary
let dic = ["":""]

//MARK:- This is variable dic means if you want to put variable 
let dic2 = ["":"", "":"", "":""]

//MARK:- Variable example
let dic3 = ["name":"Shakeel Ahmed", "imageurl":"https://abc?abc.abc/etc", "address":"Rawalpindi Pakistan"]

//MARK: - This is 2nd Variable Example dictionary
let dic4 = ["name": variablename, "city": variablecity, "zip": variablezip]

//MARK:- Dictionary String with Any Object
var dic5a = [String: String]()
//MARK:- Put values in dic
var dic5a = ["key1": "value", "key2":"value2", "key3":"value3"]

var dic5b = [String:AnyObject]()
dic5b = ["name": fullname, "imageurl": imgurl, "language": imgurl] as [String : AnyObject]

or
//MARK:- Dictionary String with Any Object
let dic5 = ["name": fullname, "imageurl": imgurl, "language": imgurl] as [String : AnyObject]

//MARK:- More Easy Way
let dic6a = NSDictionary()
let dic6b = NSMutalbeDictionary()
</code></pre>

blocks|key|111260|text|您可以使用以下代码：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|111261|var+d1+=+Dictionary<Int,+Int>()
var+d2+=+[Int:+Int]()
var+d3:+Dictionary<Int,+Int>+=+[Int+:+Int]()
var+d4:+[Int+:+Int]+=+[:]|code-block|syntax|javascript|111262|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

You can use the following code:

<pre><code>var d1 = Dictionary&lt;Int, Int&gt;()
var d2 = [Int: Int]()
var d3: Dictionary&lt;Int, Int&gt; = [Int : Int]()
var d4: [Int : Int] = [:]
</code></pre>

blocks|key|111304|text|在Swift中声明和初始化字典|type|unstyled|depth|inlineStyleRanges|entityRanges|data|111305|字符串字典|111306|var+stringDict:+[String:+String]+=+[String:+String]()|code-block|syntax|javascript|111307|或|111308|var+stringDict:+Dictionary<String,+String>+=+Dictionary<String,+String>()|111309|Int的字典|111310|var+stringDict:+[String:+Int]+=+[String:+Int]()|111311|111312|var+stringDict:+Dictionary<String,+Int>+=+Dictionary<String,+Int>()|111313|AnyObject字典|111314|var+stringDict:+[String:+AnyObject]+=+[String:+AnyObject]()|111315|111316|var+stringDict:+Dictionary<String,+AnyObject>+=+Dictionary<String,+AnyObject>()|111317|字符串数组字典|111318|var+stringDict:+[String:+[String]]+=+[String:+[String]]()|111319|111320|var+stringDict:+Dictionary<String,+Array<String>>+=+Dictionary<String,+Array<String>>()|111321|字符串字典数组|111322|var+stringDict:+[[String:+String]]+=+[[String:+String]]()|111323|111324|var+stringDict:+Array<Dictionary<String,+String>>+=+Array<Dictionary<String,+String>>()|111325|entityMap^0|0|0|0|0|0|0|0|0|0|0|0|0|0|0|0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|1G|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|1H|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|1I|8|@]|9|@]|A|$G|H]]|$1|I|3|J|5|6|7|1J|8|@]|9|@]|A|$]]|$1|K|3|L|5|F|7|1K|8|@]|9|@]|A|$G|H]]|$1|M|3|N|5|6|7|1L|8|@]|9|@]|A|$]]|$1|O|3|P|5|F|7|1M|8|@]|9|@]|A|$G|H]]|$1|Q|3|J|5|6|7|1N|8|@]|9|@]|A|$]]|$1|R|3|S|5|F|7|1O|8|@]|9|@]|A|$G|H]]|$1|T|3|U|5|6|7|1P|8|@]|9|@]|A|$]]|$1|V|3|W|5|F|7|1Q|8|@]|9|@]|A|$G|H]]|$1|X|3|J|5|6|7|1R|8|@]|9|@]|A|$]]|$1|Y|3|Z|5|F|7|1S|8|@]|9|@]|A|$G|H]]|$1|10|3|11|5|6|7|1T|8|@]|9|@]|A|$]]|$1|12|3|13|5|F|7|1U|8|@]|9|@]|A|$G|H]]|$1|14|3|J|5|6|7|1V|8|@]|9|@]|A|$]]|$1|15|3|16|5|F|7|1W|8|@]|9|@]|A|$G|H]]|$1|17|3|18|5|6|7|1X|8|@]|9|@]|A|$]]|$1|19|3|1A|5|F|7|1Y|8|@]|9|@]|A|$G|H]]|$1|1B|3|J|5|6|7|1Z|8|@]|9|@]|A|$]]|$1|1C|3|1D|5|F|7|20|8|@]|9|@]|A|$G|H]]|$1|1E|3|-4|5|6|7|21|8|@]|9|@]|A|$]]]|1F|$]]

<h1>Declaring &amp; Initializing Dictionaries in Swift</h1>

<h3>Dictionary of String</h3>

<pre><code>var stringDict: [String: String] = [String: String]()
</code></pre>

OR

<pre><code>var stringDict: Dictionary&lt;String, String&gt; = Dictionary&lt;String, String&gt;()
</code></pre>

<h3>Dictionary of Int</h3>

<pre><code>var stringDict: [String: Int] = [String: Int]()
</code></pre>

OR

<pre><code>var stringDict: Dictionary&lt;String, Int&gt; = Dictionary&lt;String, Int&gt;()
</code></pre>

<h3>Dictionary of AnyObject</h3>

<pre><code>var stringDict: [String: AnyObject] = [String: AnyObject]()
</code></pre>

OR

<pre><code>var stringDict: Dictionary&lt;String, AnyObject&gt; = Dictionary&lt;String, AnyObject&gt;()
</code></pre>

<h3>Dictionary of Array of String</h3>

<pre><code>var stringDict: [String: [String]] = [String: [String]]()
</code></pre>

OR

<pre><code>var stringDict: Dictionary&lt;String, Array&lt;String&gt;&gt; = Dictionary&lt;String, Array&lt;String&gt;&gt;()
</code></pre>

<h3>Array of Dictionaries of String</h3>

<pre><code>var stringDict: [[String: String]] = [[String: String]]()
</code></pre>

OR

<pre><code>var stringDict: Array&lt;Dictionary&lt;String, String&gt;&gt; = Array&lt;Dictionary&lt;String, String&gt;&gt;()
</code></pre>

blocks|key|4617450|text|要使用[:]+aka+the+empty+dictionary+literal创建一个空字典，实际上需要先提供上下文，就像键和值的类型一样。使用[:]创建空字典的正确方法是：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|4617451|var+dict:+[String:+Int]+=+[:]|code-block|syntax|javascript|4617452|entityMap^0|3|10|20|3|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@$9|N|A|O|B|C]|$9|P|A|Q|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|R|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|S|8|@]|D|@]|E|$]]]|L|$]]

To create an empty dictionary with the <code>[:] aka the empty dictionary literal</code>, you actually need to provide the context first as in the type of both the key and the value. The correct way to use the <code>[:]</code> to create an empty dictionary is:
<pre><code>var dict: [String: Int] = [:]
</code></pre>

I am beginning to learn <code>swift</code> by following the iBook-<code>The Swift Programming Language</code> on Swift provided by Apple. The book says to create an empty dictionary one should use <code>[:]</code> same as while declaring array as <code>[]</code>:

I declared an empty array as follows :

<pre><code>let emptyArr = [] // or String[]()
</code></pre>

But on declaring empty dictionary, I get syntax error:

<pre><code>let emptyDict = [:]
</code></pre>

How do I declare an empty dictionary?

Swift: declare an empty dictionary

编译器

Swift

我是通过在Swift上关注苹果提供的iBook-The Swift Programming Language开始学习swift的。书中说，要创建一个空字典，应该使用与将数组声明为[]时相同的[:]我声明了一个空数组，如下所示：let emptyArr = [] // or String[]()但是在声明空字典时，我得到...

问Swift:声明一个空字典
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