Dictionary<TKey,TValue> 類別(System.Collections.Generic)

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下載MicrosoftEdge 其他資訊 目錄 結束焦點模式 語言 儲存 編輯 共用 Twitter LinkedIn Facebook 電子郵件 WeChat 目錄 語言 Dictionary類別 定義 命名空間: System.Collections.Generic 組件:System.Collections.dll 組件:mscorlib.dll,System.Collections.dll 組件:mscorlib.dll,netstandard.dll 組件:mscorlib.dll 組件:netstandard.dll 表示索引鍵和值的集合。

Representsacollectionofkeysandvalues. 本文內容 generic publicrefclassDictionary:System::Collections::Generic::ICollection<:collections::generic::keyvaluepair>>,System::Collections::Generic::IDictionary,System::Collections::Generic::IEnumerable<:collections::generic::keyvaluepair>>,System::Collections::Generic::IReadOnlyCollection<:collections::generic::keyvaluepair>>,System::Collections::Generic::IReadOnlyDictionary,System::Collections::IDictionary generic publicrefclassDictionary:System::Collections::Generic::ICollection<:collections::generic::keyvaluepair>>,System::Collections::Generic::IDictionary,System::Collections::Generic::IEnumerable<:collections::generic::keyvaluepair>>,System::Collections::Generic::IReadOnlyCollection<:collections::generic::keyvaluepair>>,System::Collections::Generic::IReadOnlyDictionary,System::Collections::IDictionary,System::Runtime::Serialization::IDeserializationCallback,System::Runtime::Serialization::ISerializable generic publicrefclassDictionary:System::Collections::Generic::ICollection<:collections::generic::keyvaluepair>>,System::Collections::Generic::IDictionary,System::Collections::Generic::IEnumerable<:collections::generic::keyvaluepair>>,System::Collections::IDictionary,System::Runtime::Serialization::IDeserializationCallback,System::Runtime::Serialization::ISerializable publicclassDictionary:System.Collections.Generic.ICollection>,System.Collections.Generic.IDictionary,System.Collections.Generic.IEnumerable>,System.Collections.Generic.IReadOnlyCollection>,System.Collections.Generic.IReadOnlyDictionary,System.Collections.IDictionary publicclassDictionary:System.Collections.Generic.ICollection>,System.Collections.Generic.IDictionary,System.Collections.Generic.IEnumerable>,System.Collections.Generic.IReadOnlyCollection>,System.Collections.Generic.IReadOnlyDictionary,System.Collections.IDictionary,System.Runtime.Serialization.IDeserializationCallback,System.Runtime.Serialization.ISerializable [System.Runtime.InteropServices.ComVisible(false)] [System.Serializable] publicclassDictionary:System.Collections.Generic.ICollection>,System.Collections.Generic.IDictionary,System.Collections.Generic.IEnumerable>,System.Collections.IDictionary,System.Runtime.Serialization.IDeserializationCallback,System.Runtime.Serialization.ISerializable [System.Runtime.InteropServices.ComVisible(false)] [System.Serializable] publicclassDictionary:System.Collections.Generic.ICollection>,System.Collections.Generic.IDictionary,System.Collections.Generic.IEnumerable>,System.Collections.Generic.IReadOnlyCollection>,System.Collections.Generic.IReadOnlyDictionary,System.Collections.IDictionary,System.Runtime.Serialization.IDeserializationCallback,System.Runtime.Serialization.ISerializable typeDictionary=class interfaceICollection> interfaceseq> interfaceIEnumerable interfaceIDictionary interfaceIReadOnlyCollection> interfaceIReadOnlyDictionary interfaceICollection interfaceIDictionary typeDictionary=class interfaceICollection> interfaceseq> interfaceIEnumerable interfaceIDictionary interfaceIReadOnlyCollection> interfaceIReadOnlyDictionary interfaceICollection interfaceIDictionary interfaceIDeserializationCallback interfaceISerializable [] [] typeDictionary=class interfaceIDictionary interfaceICollection> interfaceseq> interfaceIDictionary interfaceICollection interfaceIEnumerable interfaceISerializable interfaceIDeserializationCallback [] [] typeDictionary=class interfaceIDictionary interfaceICollection> interfaceIDictionary interfaceICollection interfaceIReadOnlyDictionary interfaceIReadOnlyCollection> interfaceseq> interfaceIEnumerable interfaceISerializable interfaceIDeserializationCallback [] [] typeDictionary=class interfaceIDictionary interfaceICollection> interfaceseq> interfaceIEnumerable interfaceIDictionary interfaceICollection interfaceIReadOnlyDictionary interfaceIReadOnlyCollection> interfaceISerializable interfaceIDeserializationCallback typeDictionary=class interfaceIDictionary interfaceICollection> interfaceIReadOnlyDictionary interfaceIReadOnlyCollection> interfaceseq> interfaceIDictionary interfaceICollection interfaceIEnumerable [] [] typeDictionary=class interfaceIDictionary interfaceIDictionary interfaceIReadOnlyDictionary interfaceISerializable interfaceIDeserializationCallback interfaceICollection> interfaceseq> interfaceIEnumerable interfaceICollection interfaceIReadOnlyCollection> PublicClassDictionary(OfTKey,TValue) ImplementsICollection(OfKeyValuePair(OfTKey,TValue)),IDictionary,IDictionary(OfTKey,TValue),IEnumerable(OfKeyValuePair(OfTKey,TValue)),IReadOnlyCollection(OfKeyValuePair(OfTKey,TValue)),IReadOnlyDictionary(OfTKey,TValue) PublicClassDictionary(OfTKey,TValue) ImplementsICollection(OfKeyValuePair(OfTKey,TValue)),IDeserializationCallback,IDictionary,IDictionary(OfTKey,TValue),IEnumerable(OfKeyValuePair(OfTKey,TValue)),IReadOnlyCollection(OfKeyValuePair(OfTKey,TValue)),IReadOnlyDictionary(OfTKey,TValue),ISerializable PublicClassDictionary(OfTKey,TValue) ImplementsICollection(OfKeyValuePair(OfTKey,TValue)),IDeserializationCallback,IDictionary,IDictionary(OfTKey,TValue),IEnumerable(OfKeyValuePair(OfTKey,TValue)),ISerializable 類型參數 TKey 字典中的索引鍵類型。

Thetypeofthekeysinthedictionary. TValue 字典中的值類型。

Thetypeofthevaluesinthedictionary. 繼承 Object Dictionary 衍生 System.ServiceModel.MessageQuerySet 屬性 ComVisibleAttribute SerializableAttribute 實作 ICollection> IDictionary IEnumerable> IEnumerable IReadOnlyCollection> IReadOnlyDictionary ICollection IDictionary IEnumerable IDeserializationCallback ISerializable 範例 下列程式碼範例會使用字串索引鍵建立空Dictionary的字串，並使用Add方法來加入一些元素。

ThefollowingcodeexamplecreatesanemptyDictionaryofstringswithstringkeysandusestheAddmethodtoaddsomeelements.此範例示範AddArgumentException當嘗試加入重複的索引鍵時，方法會擲回。

TheexampledemonstratesthattheAddmethodthrowsanArgumentExceptionwhenattemptingtoaddaduplicatekey. 此範例會使用Item[]屬性(c#中的索引子)來取得值，KeyNotFoundException並示範當要求的索引鍵不存在時擲回，並顯示與索引鍵相關聯的值可以取代。

TheexampleusestheItem[]property(theindexerinC#)toretrievevalues,demonstratingthataKeyNotFoundExceptionisthrownwhenarequestedkeyisnotpresent,andshowingthatthevalueassociatedwithakeycanbereplaced. 該示例顯示如何使用TryGetValue方法作為更有效的方式來檢索值，如果程序通常必須嘗試不在字典中的鍵值，並且它顯示如何使用ContainsKey方法來測試在調用Add方法。

TheexampleshowshowtousetheTryGetValuemethodasamoreefficientwaytoretrievevaluesifaprogramoftenmusttrykeyvaluesthatarenotinthedictionary,anditshowshowtousetheContainsKeymethodtotestwhetherakeyexistsbeforecallingtheAddmethod. 此範例顯示如何列舉字典中的索引鍵和值，以及如何使用屬性和屬性單獨列舉索引鍵和值KeysValues。

TheexampleshowshowtoenumeratethekeysandvaluesinthedictionaryandhowtoenumeratethekeysandvaluesaloneusingtheKeyspropertyandtheValuesproperty. 最後，此範例會示範Remove方法。

Finally,theexampledemonstratestheRemovemethod. usingnamespaceSystem; usingnamespaceSystem::Collections::Generic; publicrefclassExample { public: staticvoidMain() { //Createanewdictionaryofstrings,withstringkeys. // Dictionary^openWith= gcnewDictionary(); //Addsomeelementstothedictionary.Thereareno //duplicatekeys,butsomeofthevaluesareduplicates. openWith->Add("txt","notepad.exe"); openWith->Add("bmp","paint.exe"); openWith->Add("dib","paint.exe"); openWith->Add("rtf","wordpad.exe"); //TheAddmethodthrowsanexceptionifthenewkeyis //alreadyinthedictionary. try { openWith->Add("txt","winword.exe"); } catch(ArgumentException^) { Console::WriteLine("AnelementwithKey=\"txt\"alreadyexists."); } //TheItempropertyisanothernamefortheindexer,soyou //canomititsnamewhenaccessingelements. Console::WriteLine("Forkey=\"rtf\",value={0}.", openWith["rtf"]); //Theindexercanbeusedtochangethevalueassociated //withakey. openWith["rtf"]="winword.exe"; Console::WriteLine("Forkey=\"rtf\",value={0}.", openWith["rtf"]); //Ifakeydoesnotexist,settingtheindexerforthatkey //addsanewkey/valuepair. openWith["doc"]="winword.exe"; //Theindexerthrowsanexceptioniftherequestedkeyis //notinthedictionary. try { Console::WriteLine("Forkey=\"tif\",value={0}.", openWith["tif"]); } catch(KeyNotFoundException^) { Console::WriteLine("Key=\"tif\"isnotfound."); } //Whenaprogramoftenhastotrykeysthatturnoutnotto //beinthedictionary,TryGetValuecanbeamoreefficient //waytoretrievevalues. String^value=""; if(openWith->TryGetValue("tif",value)) { Console::WriteLine("Forkey=\"tif\",value={0}.",value); } else { Console::WriteLine("Key=\"tif\"isnotfound."); } //ContainsKeycanbeusedtotestkeysbeforeinserting //them. if(!openWith->ContainsKey("ht")) { openWith->Add("ht","hypertrm.exe"); Console::WriteLine("Valueaddedforkey=\"ht\":{0}", openWith["ht"]); } //Whenyouuseforeachtoenumeratedictionaryelements, //theelementsareretrievedasKeyValuePairobjects. Console::WriteLine(); foreach(KeyValuePairkvpinopenWith) { Console::WriteLine("Key={0},Value={1}", kvp.Key,kvp.Value); } //Togetthevaluesalone,usetheValuesproperty. Dictionary::ValueCollection^valueColl= openWith->Values; //TheelementsoftheValueCollectionarestronglytyped //withthetypethatwasspecifiedfordictionaryvalues. Console::WriteLine(); foreach(String^sinvalueColl) { Console::WriteLine("Value={0}",s); } //Togetthekeysalone,usetheKeysproperty. Dictionary::KeyCollection^keyColl= openWith->Keys; //TheelementsoftheKeyCollectionarestronglytyped //withthetypethatwasspecifiedfordictionarykeys. Console::WriteLine(); foreach(String^sinkeyColl) { Console::WriteLine("Key={0}",s); } //UsetheRemovemethodtoremoveakey/valuepair. Console::WriteLine("\nRemove(\"doc\")"); openWith->Remove("doc"); if(!openWith->ContainsKey("doc")) { Console::WriteLine("Key\"doc\"isnotfound."); } } }; intmain() { Example::Main(); } /*Thiscodeexampleproducesthefollowingoutput: AnelementwithKey="txt"alreadyexists. Forkey="rtf",value=wordpad.exe. Forkey="rtf",value=winword.exe. Key="tif"isnotfound. Key="tif"isnotfound. Valueaddedforkey="ht":hypertrm.exe Key=txt,Value=notepad.exe Key=bmp,Value=paint.exe Key=dib,Value=paint.exe Key=rtf,Value=winword.exe Key=doc,Value=winword.exe Key=ht,Value=hypertrm.exe Value=notepad.exe Value=paint.exe Value=paint.exe Value=winword.exe Value=winword.exe Value=hypertrm.exe Key=txt Key=bmp Key=dib Key=rtf Key=doc Key=ht Remove("doc") Key"doc"isnotfound. */ //Createanewdictionaryofstrings,withstringkeys. // DictionaryopenWith= newDictionary(); //Addsomeelementstothedictionary.Thereareno //duplicatekeys,butsomeofthevaluesareduplicates. openWith.Add("txt","notepad.exe"); openWith.Add("bmp","paint.exe"); openWith.Add("dib","paint.exe"); openWith.Add("rtf","wordpad.exe"); //TheAddmethodthrowsanexceptionifthenewkeyis //alreadyinthedictionary. try { openWith.Add("txt","winword.exe"); } catch(ArgumentException) { Console.WriteLine("AnelementwithKey=\"txt\"alreadyexists."); } //TheItempropertyisanothernamefortheindexer,soyou //canomititsnamewhenaccessingelements. Console.WriteLine("Forkey=\"rtf\",value={0}.", openWith["rtf"]); //Theindexercanbeusedtochangethevalueassociated //withakey. openWith["rtf"]="winword.exe"; Console.WriteLine("Forkey=\"rtf\",value={0}.", openWith["rtf"]); //Ifakeydoesnotexist,settingtheindexerforthatkey //addsanewkey/valuepair. openWith["doc"]="winword.exe"; //Theindexerthrowsanexceptioniftherequestedkeyis //notinthedictionary. try { Console.WriteLine("Forkey=\"tif\",value={0}.", openWith["tif"]); } catch(KeyNotFoundException) { Console.WriteLine("Key=\"tif\"isnotfound."); } //Whenaprogramoftenhastotrykeysthatturnoutnotto //beinthedictionary,TryGetValuecanbeamoreefficient //waytoretrievevalues. stringvalue=""; if(openWith.TryGetValue("tif",outvalue)) { Console.WriteLine("Forkey=\"tif\",value={0}.",value); } else { Console.WriteLine("Key=\"tif\"isnotfound."); } //ContainsKeycanbeusedtotestkeysbeforeinserting //them. if(!openWith.ContainsKey("ht")) { openWith.Add("ht","hypertrm.exe"); Console.WriteLine("Valueaddedforkey=\"ht\":{0}", openWith["ht"]); } //Whenyouuseforeachtoenumeratedictionaryelements, //theelementsareretrievedasKeyValuePairobjects. Console.WriteLine(); foreach(KeyValuePairkvpinopenWith) { Console.WriteLine("Key={0},Value={1}", kvp.Key,kvp.Value); } //Togetthevaluesalone,usetheValuesproperty. Dictionary.ValueCollectionvalueColl= openWith.Values; //TheelementsoftheValueCollectionarestronglytyped //withthetypethatwasspecifiedfordictionaryvalues. Console.WriteLine(); foreach(stringsinvalueColl) { Console.WriteLine("Value={0}",s); } //Togetthekeysalone,usetheKeysproperty. Dictionary.KeyCollectionkeyColl= openWith.Keys; //TheelementsoftheKeyCollectionarestronglytyped //withthetypethatwasspecifiedfordictionarykeys. Console.WriteLine(); foreach(stringsinkeyColl) { Console.WriteLine("Key={0}",s); } //UsetheRemovemethodtoremoveakey/valuepair. Console.WriteLine("\nRemove(\"doc\")"); openWith.Remove("doc"); if(!openWith.ContainsKey("doc")) { Console.WriteLine("Key\"doc\"isnotfound."); } /*Thiscodeexampleproducesthefollowingoutput: AnelementwithKey="txt"alreadyexists. Forkey="rtf",value=wordpad.exe. Forkey="rtf",value=winword.exe. Key="tif"isnotfound. Key="tif"isnotfound. Valueaddedforkey="ht":hypertrm.exe Key=txt,Value=notepad.exe Key=bmp,Value=paint.exe Key=dib,Value=paint.exe Key=rtf,Value=winword.exe Key=doc,Value=winword.exe Key=ht,Value=hypertrm.exe Value=notepad.exe Value=paint.exe Value=paint.exe Value=winword.exe Value=winword.exe Value=hypertrm.exe Key=txt Key=bmp Key=dib Key=rtf Key=doc Key=ht Remove("doc") Key"doc"isnotfound. */ ImportsSystem.Collections.Generic PublicClassExample PublicSharedSubMain() 'Createanewdictionaryofstrings,withstringkeys. ' DimopenWithAsNewDictionary(OfString,String) 'Addsomeelementstothedictionary.Thereareno 'duplicatekeys,butsomeofthevaluesareduplicates. openWith.Add("txt","notepad.exe") openWith.Add("bmp","paint.exe") openWith.Add("dib","paint.exe") openWith.Add("rtf","wordpad.exe") 'TheAddmethodthrowsanexceptionifthenewkeyis 'alreadyinthedictionary. Try openWith.Add("txt","winword.exe") Catch Console.WriteLine("AnelementwithKey=""txt""alreadyexists.") EndTry 'TheItempropertyisthedefaultproperty,soyou 'canomititsnamewhenaccessingelements. Console.WriteLine("Forkey=""rtf"",value={0}.",_ openWith("rtf")) 'ThedefaultItempropertycanbeusedtochangethevalue 'associatedwithakey. openWith("rtf")="winword.exe" Console.WriteLine("Forkey=""rtf"",value={0}.",_ openWith("rtf")) 'Ifakeydoesnotexist,settingthedefaultItemproperty 'forthatkeyaddsanewkey/valuepair. openWith("doc")="winword.exe" 'ThedefaultItempropertythrowsanexceptioniftherequested 'keyisnotinthedictionary. Try Console.WriteLine("Forkey=""tif"",value={0}.",_ openWith("tif")) Catch Console.WriteLine("Key=""tif""isnotfound.") EndTry 'Whenaprogramoftenhastotrykeysthatturnoutnotto 'beinthedictionary,TryGetValuecanbeamoreefficient 'waytoretrievevalues. DimvalueAsString="" IfopenWith.TryGetValue("tif",value)Then Console.WriteLine("Forkey=""tif"",value={0}.",value) Else Console.WriteLine("Key=""tif""isnotfound.") EndIf 'ContainsKeycanbeusedtotestkeysbeforeinserting 'them. IfNotopenWith.ContainsKey("ht")Then openWith.Add("ht","hypertrm.exe") Console.WriteLine("Valueaddedforkey=""ht"":{0}",_ openWith("ht")) EndIf 'Whenyouuseforeachtoenumeratedictionaryelements, 'theelementsareretrievedasKeyValuePairobjects. Console.WriteLine() ForEachkvpAsKeyValuePair(OfString,String)InopenWith Console.WriteLine("Key={0},Value={1}",_ kvp.Key,kvp.Value) Nextkvp 'Togetthevaluesalone,usetheValuesproperty. DimvalueCollAs_ Dictionary(OfString,String).ValueCollection=_ openWith.Values 'TheelementsoftheValueCollectionarestronglytyped 'withthetypethatwasspecifiedfordictionaryvalues. Console.WriteLine() ForEachsAsStringInvalueColl Console.WriteLine("Value={0}",s) Nexts 'Togetthekeysalone,usetheKeysproperty. DimkeyCollAs_ Dictionary(OfString,String).KeyCollection=_ openWith.Keys 'TheelementsoftheKeyCollectionarestronglytyped 'withthetypethatwasspecifiedfordictionarykeys. Console.WriteLine() ForEachsAsStringInkeyColl Console.WriteLine("Key={0}",s) Nexts 'UsetheRemovemethodtoremoveakey/valuepair. Console.WriteLine(vbLf+"Remove(""doc"")") openWith.Remove("doc") IfNotopenWith.ContainsKey("doc")Then Console.WriteLine("Key""doc""isnotfound.") EndIf EndSub EndClass 'Thiscodeexampleproducesthefollowingoutput: ' 'AnelementwithKey="txt"alreadyexists. 'Forkey="rtf",value=wordpad.exe. 'Forkey="rtf",value=winword.exe. 'Key="tif"isnotfound. 'Key="tif"isnotfound. 'Valueaddedforkey="ht":hypertrm.exe ' 'Key=txt,Value=notepad.exe 'Key=bmp,Value=paint.exe 'Key=dib,Value=paint.exe 'Key=rtf,Value=winword.exe 'Key=doc,Value=winword.exe 'Key=ht,Value=hypertrm.exe ' 'Value=notepad.exe 'Value=paint.exe 'Value=paint.exe 'Value=winword.exe 'Value=winword.exe 'Value=hypertrm.exe ' 'Key=txt 'Key=bmp 'Key=dib 'Key=rtf 'Key=doc 'Key=ht ' 'Remove("doc") 'Key"doc"isnotfound. ' 備註 Dictionary泛型類別會提供一組索引鍵與一組值的對應。

TheDictionarygenericclassprovidesamappingfromasetofkeystoasetofvalues.加入字典中的每一個項目都是由值及其關聯索引鍵所組成。

Eachadditiontothedictionaryconsistsofavalueanditsassociatedkey.使用索引鍵來抓取值相當快速，接近O(1)，因為該Dictionary類別會實作為雜湊表。

Retrievingavaluebyusingitskeyisveryfast,closetoO(1),becausetheDictionaryclassisimplementedasahashtable. 注意 抓取的速度取決於所指定之類型的雜湊演算法品質TKey。

ThespeedofretrievaldependsonthequalityofthehashingalgorithmofthetypespecifiedforTKey. 只要將物件當做中的索引鍵使用Dictionary，它就不能以任何影響其雜湊值的方式變更。

AslongasanobjectisusedasakeyintheDictionary,itmustnotchangeinanywaythataffectsitshashvalue.中的每個索引鍵都Dictionary必須是唯一的，根據字典的相等比較子。

EverykeyinaDictionarymustbeuniqueaccordingtothedictionary'sequalitycomparer.索引鍵不能是null，但如果其型別TValue是參考型別，則其值可以是。

Akeycannotbenull,butavaluecanbe,ifitstypeTValueisareferencetype. Dictionary需要相等的執行，以判斷索引鍵是否相等。

Dictionaryrequiresanequalityimplementationtodeterminewhetherkeysareequal.您可以使用接受參數的函式來指定泛型介面的實值IEqualityComparercomparer;如果您沒有指定執行，則會使用預設的泛型相等比較子EqualityComparer.Default。

YoucanspecifyanimplementationoftheIEqualityComparergenericinterfacebyusingaconstructorthatacceptsacomparerparameter;ifyoudonotspecifyanimplementation,thedefaultgenericequalitycomparerEqualityComparer.Defaultisused.如果類型TKeySystem.IEquatable會實作為泛型介面，則預設的相等比較子會使用該執行。

IftypeTKeyimplementstheSystem.IEquatablegenericinterface,thedefaultequalitycomparerusesthatimplementation. 注意 例如，您可以使用類別提供的不區分大小寫字串比較子StringComparer來建立具有不區分大小寫字串索引鍵的字典。

Forexample,youcanusethecase-insensitivestringcomparersprovidedbytheStringComparerclasstocreatedictionarieswithcase-insensitivestringkeys. 的容量Dictionary是可保存的元素數目Dictionary。

ThecapacityofaDictionaryisthenumberofelementstheDictionarycanhold.當專案加入至時Dictionary，會依需要重新配置內部陣列來自動增加容量。

AselementsareaddedtoaDictionary,thecapacityisautomaticallyincreasedasrequiredbyreallocatingtheinternalarray. 僅.NETFramework：針對非常大的Dictionary物件，您可以在enabledtrue執行時間環境中將設定元素的屬性設定為，以增加64位系統上2000000000元素的最大容量。

.NETFrameworkonly:ForverylargeDictionaryobjects,youcanincreasethemaximumcapacityto2billionelementsona64-bitsystembysettingtheenabledattributeoftheconfigurationelementtotrueintherun-timeenvironment. 基於列舉的目的，字典中的每個專案都會被視為KeyValuePair代表值和其索引鍵的結構。

Forpurposesofenumeration,eachiteminthedictionaryistreatedasaKeyValuePairstructurerepresentingavalueanditskey.傳回專案的順序未定義。

Theorderinwhichtheitemsarereturnedisundefined. Cforeach++中的c#語言(的語句foreach，ForEach在VisualBasic)會傳回集合中元素類型的物件。

TheforeachstatementoftheC#language(foreachinC++,ForEachinVisualBasic)returnsanobjectofthetypeoftheelementsinthecollection.由於Dictionary是索引鍵和值的集合，因此元素類型不是索引鍵的類型或值的型別。

SincetheDictionaryisacollectionofkeysandvalues,theelementtypeisnotthetypeofthekeyorthetypeofthevalue.相反地，元素類型是索引KeyValuePair鍵類型和數值型別的。

Instead,theelementtypeisaKeyValuePairofthekeytypeandthevaluetype.例如：Forexample: foreach(KeyValuePairkvpinmyDictionary) { Console::WriteLine("Key={0},Value={1}",kvp.Key,kvp.Value); } foreach(KeyValuePairkvpinmyDictionary) { Console.WriteLine("Key={0},Value={1}",kvp.Key,kvp.Value); } ForEachkvpAsKeyValuePair(OfString,String)InmyDictionary Console.WriteLine("Key={0},Value={1}",kvp.Key,kvp.Value) Nextkvp foreach語句是列舉值周圍的包裝函式，它只允許從集合讀取，而不是寫入它。

Theforeachstatementisawrapperaroundtheenumerator,whichallowsonlyreadingfromthecollection,notwritingtoit. 注意 因為索引鍵可以繼承並變更其行為，所以使用方法的比較無法保證其絕對唯一性Equals。

Becausekeyscanbeinheritedandtheirbehaviorchanged,theirabsoluteuniquenesscannotbeguaranteedbycomparisonsusingtheEqualsmethod. 建構函式 Dictionary() 初始化Dictionary類別的新執行個體，這個執行個體是空白的、具有預設的初始容量，並使用索引鍵類型的預設相等比較子。

InitializesanewinstanceoftheDictionaryclassthatisempty,hasthedefaultinitialcapacity,andusesthedefaultequalitycomparerforthekeytype. Dictionary(IDictionary) 初始化Dictionary類別的新執行個體，其中包含從指定的IDictionary複製的項目，並使用索引鍵類型的預設相等比較子。

InitializesanewinstanceoftheDictionaryclassthatcontainselementscopiedfromthespecifiedIDictionaryandusesthedefaultequalitycomparerforthekeytype. Dictionary(IDictionary,IEqualityComparer) 初始化Dictionary類別的新執行個體，其中包含從指定的IDictionary複製的項目，並使用指定的IEqualityComparer。

InitializesanewinstanceoftheDictionaryclassthatcontainselementscopiedfromthespecifiedIDictionaryandusesthespecifiedIEqualityComparer. Dictionary(IEnumerable>) 初始化Dictionary類別的新執行個體，這個類別包含從指定的IEnumerable所複製項目。

InitializesanewinstanceoftheDictionaryclassthatcontainselementscopiedfromthespecifiedIEnumerable. Dictionary(IEnumerable>,IEqualityComparer) 初始化Dictionary類別的新執行個體，其中包含從指定的IEnumerable複製的項目，並使用指定的IEqualityComparer。

InitializesanewinstanceoftheDictionaryclassthatcontainselementscopiedfromthespecifiedIEnumerableandusesthespecifiedIEqualityComparer. Dictionary(IEqualityComparer) 初始化Dictionary類別的新執行個體，這個執行個體是空白的、具有預設的初始容量，並使用指定的IEqualityComparer。

InitializesanewinstanceoftheDictionaryclassthatisempty,hasthedefaultinitialcapacity,andusesthespecifiedIEqualityComparer. Dictionary(Int32) 初始化Dictionary類別的新執行個體，這個執行個體是空白的、具有指定的初始容量，並使用索引鍵類型的預設相等比較子。

InitializesanewinstanceoftheDictionaryclassthatisempty,hasthespecifiedinitialcapacity,andusesthedefaultequalitycomparerforthekeytype. Dictionary(Int32,IEqualityComparer) 初始化Dictionary類別的新執行個體，這個執行個體是空白的、具有指定的初始容量，並使用指定的IEqualityComparer。

InitializesanewinstanceoftheDictionaryclassthatisempty,hasthespecifiedinitialcapacity,andusesthespecifiedIEqualityComparer. Dictionary(SerializationInfo,StreamingContext) 使用序列化資料，初始化Dictionary類別的新執行個體。

InitializesanewinstanceoftheDictionaryclasswithserializeddata. 屬性 Comparer 取得IEqualityComparer，用來判斷字典的索引鍵是否相等。

GetstheIEqualityComparerthatisusedtodetermineequalityofkeysforthedictionary. Count 取得Dictionary中所包含的索引鍵/值組數目。

Getsthenumberofkey/valuepairscontainedintheDictionary. Item[TKey] 取得或設定與指定之索引鍵相關聯的值。

Getsorsetsthevalueassociatedwiththespecifiedkey. Keys 取得集合，包含Dictionary中的索引鍵。

GetsacollectioncontainingthekeysintheDictionary. Values 取得集合，包含Dictionary中的值。

GetsacollectioncontainingthevaluesintheDictionary. 方法 Add(TKey,TValue) 將指定的索引鍵和值加入字典。

Addsthespecifiedkeyandvaluetothedictionary. Clear() 從Dictionary移除所有索引鍵和值。

RemovesallkeysandvaluesfromtheDictionary. ContainsKey(TKey) 判斷Dictionary是否包含特定索引鍵。

DetermineswhethertheDictionarycontainsthespecifiedkey. ContainsValue(TValue) 判斷Dictionary是否包含特定值。

DetermineswhethertheDictionarycontainsaspecificvalue. EnsureCapacity(Int32) 確保字典最多可以保留指定的項目數量，但不必進一步擴充其支援儲存體。

Ensuresthatthedictionarycanholduptoaspecifiednumberofentrieswithoutanyfurtherexpansionofitsbackingstorage. Equals(Object) 判斷指定的物件是否等於目前的物件。

Determineswhetherthespecifiedobjectisequaltothecurrentobject. (繼承來源Object) GetEnumerator() 傳回在Dictionary中逐一查看的列舉值。

ReturnsanenumeratorthatiteratesthroughtheDictionary. GetHashCode() 做為預設雜湊函式。

Servesasthedefaulthashfunction. (繼承來源Object) GetObjectData(SerializationInfo,StreamingContext) 實作ISerializable介面，並傳回序列化Dictionary執行個體所需的資料。

ImplementstheISerializableinterfaceandreturnsthedataneededtoserializetheDictionaryinstance. GetType() 取得目前執行個體的Type。

GetstheTypeofthecurrentinstance. (繼承來源Object) MemberwiseClone() 建立目前Object的淺層複製。

CreatesashallowcopyofthecurrentObject. (繼承來源Object) OnDeserialization(Object) 實作ISerializable介面，並於還原序列化完成時引發還原序列化事件。

ImplementstheISerializableinterfaceandraisesthedeserializationeventwhenthedeserializationiscomplete. Remove(TKey) 將具有指定索引鍵的值從Dictionary中移除。

RemovesthevaluewiththespecifiedkeyfromtheDictionary. Remove(TKey,TValue) 從Dictionary中移除具有指定索引鍵的值，並將該項目複製到value參數。

RemovesthevaluewiththespecifiedkeyfromtheDictionary,andcopiestheelementtothevalueparameter. ToString() 傳回代表目前物件的字串。

Returnsastringthatrepresentsthecurrentobject. (繼承來源Object) TrimExcess() 將此字典容量設定為一開始若使用所有項目初始化的應有容量。

Setsthecapacityofthisdictionarytowhatitwouldbeifithadbeenoriginallyinitializedwithallitsentries. TrimExcess(Int32) 將此字典容量設定為最多可以保留的指定項目數量，但不必進一步擴充其支援儲存體。

Setsthecapacityofthisdictionarytoholdupaspecifiednumberofentrieswithoutanyfurtherexpansionofitsbackingstorage. TryAdd(TKey,TValue) 嘗試將指定的索引鍵和值新增至字典。

Attemptstoaddthespecifiedkeyandvaluetothedictionary. TryGetValue(TKey,TValue) 取得與指定索引鍵關聯的值。

Getsthevalueassociatedwiththespecifiedkey. 明確介面實作 ICollection.CopyTo(Array,Int32) 從指定的陣列索引處開始，將ICollection的項目複製到陣列。

CopiestheelementsoftheICollectiontoanarray,startingatthespecifiedarrayindex. ICollection.IsSynchronized 取得值，這個值會指出ICollection的存取是否同步(具備安全執行緒)。

GetsavaluethatindicateswhetheraccesstotheICollectionissynchronized(threadsafe). ICollection.SyncRoot 取得可用以同步存取ICollection的物件。

GetsanobjectthatcanbeusedtosynchronizeaccesstotheICollection. ICollection>.Add(KeyValuePair) 將指定的值加入具有指定索引鍵的ICollection。

AddsthespecifiedvaluetotheICollectionwiththespecifiedkey. ICollection>.Contains(KeyValuePair) 判斷ICollection是否包含特定索引鍵和值。

DetermineswhethertheICollectioncontainsaspecifickeyandvalue. ICollection>.CopyTo(KeyValuePair[],Int32) 從指定的陣列索引處開始，將ICollection的項目複製到KeyValuePair類型的陣列。

CopiestheelementsoftheICollectiontoanarrayoftypeKeyValuePair,startingatthespecifiedarrayindex. ICollection>.IsReadOnly 取得值，這個值表示字典是否為唯讀。

Getsavaluethatindicateswhetherthedictionaryisread-only. ICollection>.Remove(KeyValuePair) 從字典移除索引鍵和值。

Removesakeyandvaluefromthedictionary. IDictionary.Add(Object,Object) 將指定的索引鍵和值加入字典。

Addsthespecifiedkeyandvaluetothedictionary. IDictionary.Contains(Object) 判斷IDictionary是否包含具有指定之索引鍵的項目。

DetermineswhethertheIDictionarycontainsanelementwiththespecifiedkey. IDictionary.GetEnumerator() 傳回IDictionaryEnumerator的IDictionary。

ReturnsanIDictionaryEnumeratorfortheIDictionary. IDictionary.IsFixedSize 取得值，指出IDictionary是否有固定的大小。

GetsavaluethatindicateswhethertheIDictionaryhasafixedsize. IDictionary.IsReadOnly 取得值，這個值表示IDictionary是否為唯讀。

GetsavaluethatindicateswhethertheIDictionaryisread-only. IDictionary.Item[Object] 取得或設定具有指定之索引鍵的值。

Getsorsetsthevaluewiththespecifiedkey. IDictionary.Keys 取得ICollection，包含IDictionary的索引鍵。

GetsanICollectioncontainingthekeysoftheIDictionary. IDictionary.Remove(Object) 從IDictionary中移除具有指定之索引鍵的項目。

RemovestheelementwiththespecifiedkeyfromtheIDictionary. IDictionary.Values 取得ICollection，包含IDictionary中的值。

GetsanICollectioncontainingthevaluesintheIDictionary. IDictionary.Keys 取得ICollection，包含IDictionary的索引鍵。

GetsanICollectioncontainingthekeysoftheIDictionary. IDictionary.Values 取得ICollection，包含IDictionary中的值。

GetsanICollectioncontainingthevaluesintheIDictionary. IEnumerable.GetEnumerator() 傳回逐一查看集合的列舉值。

Returnsanenumeratorthatiteratesthroughthecollection. IEnumerable>.GetEnumerator() 傳回逐一查看集合的列舉值。

Returnsanenumeratorthatiteratesthroughthecollection. IReadOnlyDictionary.Keys 取得集合，其中包含IReadOnlyDictionary的索引鍵。

GetsacollectioncontainingthekeysoftheIReadOnlyDictionary. IReadOnlyDictionary.Values 取得集合，其中包含IReadOnlyDictionary的值。

GetsacollectioncontainingthevaluesoftheIReadOnlyDictionary. 擴充方法 GetValueOrDefault(IReadOnlyDictionary,TKey) 嘗試取得與dictionary中所指定key建立關聯的值。

Triestogetthevalueassociatedwiththespecifiedkeyinthedictionary. GetValueOrDefault(IReadOnlyDictionary,TKey,TValue) 嘗試取得與dictionary中所指定索引鍵建立關聯的值。

Triestogetthevalueassociatedwiththespecifiedkeyinthedictionary. Remove(IDictionary,TKey,TValue) 嘗試從dictionary中移除具有所指定key的值。

Triestoremovethevaluewiththespecifiedkeyfromthedictionary. TryAdd(IDictionary,TKey,TValue) 嘗試將指定的key和value新增至dictionary。

Triestoaddthespecifiedkeyandvaluetothedictionary. ToImmutableArray(IEnumerable) 從指定的集合建立不可變的陣列。

Createsanimmutablearrayfromthespecifiedcollection. ToImmutableDictionary(IEnumerable,Func) 從現有的項目集合建構不可變的字典，將轉換函式套用至來源索引鍵。

Constructsanimmutabledictionaryfromanexistingcollectionofelements,applyingatransformationfunctiontothesourcekeys. ToImmutableDictionary(IEnumerable,Func,IEqualityComparer) 根據序列的某些轉換來建構不可變的字典。

Constructsanimmutabledictionarybasedonsometransformationofasequence. ToImmutableDictionary(IEnumerable,Func,Func) 列舉及轉換序列，並產生其內容的不可變字典。

Enumeratesandtransformsasequence,andproducesanimmutabledictionaryofitscontents. ToImmutableDictionary(IEnumerable,Func,Func