WebFeb 1, 2024 · The foreach statement of the C# language hides the complexity of the enumerators. Therefore, using foreach is recommended, instead of directly manipulating the enumerator. Enumerators can be used to read the data in the collection, but they cannot be used to modify the underlying collection. WebSep 15, 2024 · To enumerate directories and files, use methods that return an enumerable collection of directory or file names, or their DirectoryInfo, FileInfo, or FileSystemInfo objects. If you want to search and return only the names of directories or files, use the enumeration methods of the Directory class.
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WebMar 14, 2013 · public static IEnumerable> Batch ( this IEnumerable source, int size) { T [] bucket = null; var count = 0; foreach (var item in source) { if (bucket == null) bucket = new T [size]; bucket [count++] = item; if (count != size) continue; yield return bucket.Select (x => x); bucket = null; count = 0; } // Return the last bucket with all remaining … WebI'm trying to determine how to access the data that is in my JObject and I can't for the life of me determine how to use it. JObject Object = (JObject)Response.Data["my_key"]; I can print it to the
WebEnumerateFiles (String, String, EnumerationOptions) Returns an enumerable collection of full file names that match a search pattern and enumeration options in a specified path, and optionally searches subdirectories. C#. public static System.Collections.Generic.IEnumerable EnumerateFiles (string path, string … WebMar 24, 2009 · 4 Answers. Sorted by: 92. To enumerate a dictionary you either enumerate the values within it: Dictionary dic; foreach (string s in dic.Values) { Console.WriteLine (s); } or the KeyValuePairs. foreach (KeyValuePair kvp in dic) { Console.WriteLine ("Key : " + kvp.Key.ToString () + ", Value : " + kvp.Value); } or …
WebSep 8, 2024 · To use the Parallel.ForEach loop with a non-generic collection, you can use the Enumerable.Cast extension method to convert the collection to a generic collection, as shown in the following example: C# Parallel.ForEach (nonGenericCollection.Cast (), currentElement => { });WebC# SQL数据库中大量记录的Linq查询和Foreach,c#,entity-framework,linq,C#,Entity Framework,Linq,我正在使用实体框架和Linq。我需要对我的对象的两个属性进行查询 我在数据库中有这个对象，大约有200000条记录： public class DeviceState { public int ID { get; set; } public DateTime TimeStamp { get; set; } public string StatusCode { get; set ...WebAug 20, 2024 · The foreach loop iterate only in forward direction. Performance wise foreach loop takes much time as compared with for loop. Because internally it uses extra …WebYou can adjust the implementation depending on how you want to handle the case where the two enumerations (or lists) have different lengths; this one continues to the end of the longer enumeration, returning the default values …WebSep 15, 2024 · To enumerate directories and files, use methods that return an enumerable collection of directory or file names, or their DirectoryInfo, FileInfo, or FileSystemInfo objects. If you want to search and return only the names of directories or files, use the enumeration methods of the Directory class.WebEnumerateFiles (String, String, EnumerationOptions) Returns an enumerable collection of full file names that match a search pattern and enumeration options in a specified path, and optionally searches subdirectories. C#. public static System.Collections.Generic.IEnumerable EnumerateFiles (string path, string …Webvar Items= new List () {"s1","s2"}; Enumerate (Items); void Enumerate (object items) { //i know the type so i can cast and enumerate foreach (var item in (List) items) { } // i don't know the type of object in the list //Following won't work , can't cast to List foreach (var item in (List) items) { } }WebMar 28, 2024 · 编写高质量c#代码的10个建议. 1、使用有意义且见名知义的变量名. 这个建议也是各个研发经理代码规范的要求之一，这个建议能让代码更清晰易读，因为有意义的 …WebDec 31, 2024 · int i = 0; foreach (var f in familyListss) { familyData.Add (i, f); i++; } With a small extension method, you can build in an index to foreach to make it one line. Extension methods are worth exploring, and can take annoying, repeated tasks out of your way. Also see this question: C# Convert List to Dictionary ShareWebMar 14, 2013 · public static IEnumerable> Batch ( this IEnumerable source, int size) { T [] bucket = null; var count = 0; foreach (var item in source) { if (bucket == null) bucket = new T [size]; bucket [count++] = item; if (count != size) continue; yield return bucket.Select (x => x); bucket = null; count = 0; } // Return the last bucket with all remaining …WebApr 11, 2024 · The foreach statement: enumerates the elements of a collection and executes its body for each element of the collection. The do statement: conditionally executes its body one or more times. The while statement: conditionally executes its body zero or more times.WebApr 2, 2013 · foreach loop returns each element of a collection in the order it is called in the enumeration. foreach provides in order element access from a collection; it does not accept index and provides access to elements, so …WebApr 14, 2024 · string[] fruits = input.Split(delimiterChars, 3); foreach (string fruit in fruits) {. Console.WriteLine(fruit); } } } We use the Split method to split a string into an array of substrings based on an array of delimiter characters. We limit the number of substrings returned to 3 and output each element to the console.Web只有当我知道foreach中会发生一些需要时间或可能需要时间的重要事情时，我才使用并行foreach，比如数据库连接或向web服务发送大量数据。 如果它只是在服务器上处理信息，就像从已经加载到内存中的集合中获取ID一样，那么它真的不值得这样做。WebJun 8, 2024 · Sometimes, when looping over a collection of elements in C#, you need not only the items itself, but also its position in the collection. ... How to get the index of the current element in a foreach loop? The easiest way is to store and update the index in a separate variable. List< string > myFriends = new List< string > ...WebOct 31, 2008 · Example: if you use the LINQ extension method Reverse () on IEnumerable, which uses yield return to give the collection in reverse order, then doing a foreach (var myThing in myCollection.Reverse ()) will enumerate through the collection in reverse order. Important: yield return is key.WebWhen you say for-each in the context of C# List, there are two different ways, namely forEach statement and ForEach () method. forEach statement is a C# generic …WebSep 15, 2024 · C# int[] numbers = { 4, 5, 6, 1, 2, 3, -2, -1, 0 }; foreach (int i in numbers) { System.Console.Write (" {0} ", i); } // Output: 4 5 6 1 2 3 -2 -1 0 For multi-dimensional …WebSep 4, 2008 · The foreach is for iterating over collections that implement IEnumerable. It does this by calling GetEnumerator on the collection, which will return an Enumerator. This Enumerator has a method and a property: MoveNext () Current Current returns the object that Enumerator is currently on, MoveNext updates Current to the next object.WebFeb 28, 2024 · The Enum.The GetValues method returns an array of all enum values. The following code snippet loops through all values of an enum and prints them on the Console. foreach (int i in Enum.GetValues(typeof(Colors))) { Console.WriteLine($" {i}" ); } The Enum.The GetName method returns the constant's name in the specified enum with the …WebMar 24, 2009 · 4 Answers. Sorted by: 92. To enumerate a dictionary you either enumerate the values within it: Dictionary dic; foreach (string s in dic.Values) { Console.WriteLine (s); } or the KeyValuePairs. foreach (KeyValuePair kvp in dic) { Console.WriteLine ("Key : " + kvp.Key.ToString () + ", Value : " + kvp.Value); } or …WebLINQ doesn't have a ForEach method, and for good reason. LINQ is for performing queries.It is designed to get information from some data source. It is not designed to mutate data sources. LINQ queries shouldn't cause side …WebI'm trying to determine how to access the data that is in my JObject and I can't for the life of me determine how to use it. JObject Object = (JObject)Response.Data["my_key"]; I can print it to theWebOct 9, 2008 · I have an enumeration as follows: public enum RoleType {Administrator, Collaborator,...} How can I loop through each item in the enumeration and use it's …WebMar 28, 2024 · 编写高质量c#代码的10个建议. 1、使用有意义且见名知义的变量名. 这个建议也是各个研发经理代码规范的要求之一，这个建议能让代码更清晰易读，因为有意义的变量名可以更好地表达代码的含义，让代码更易于维护和修改。WebJan 9, 2024 · In C#, iterators are called enumerators, and they come from the IEnumerator interface. Basically, this interface provides a MoveNext() method, which goes for the next …WebJun 14, 2024 · You can just foreach the List private IEnumerable UpdateQueries (MySqlConnection connection, List queries) { foreach (var query in queries) { MySqlCommand command = new MySqlCommand (); command.Connection = connection; command.CommandText = query; command.ExecuteNonQuery (); yield return query; } } … Webvar Items= new List () {"s1","s2"}; Enumerate (Items); void Enumerate (object items) { //i know the type so i can cast and enumerate foreach (var item in (List) items) { } // i don't know the type of object in the list //Following won't work , can't cast to List foreach (var item in (List) items) { } }WebMar 28, 2024 · 编写高质量c#代码的10个建议. 1、使用有意义且见名知义的变量名. 这个建议也是各个研发经理代码规范的要求之一，这个建议能让代码更清晰易读，因为有意义的 …WebDec 31, 2024 · int i = 0; foreach (var f in familyListss) { familyData.Add (i, f); i++; } With a small extension method, you can build in an index to foreach to make it one line. Extension methods are worth exploring, and can take annoying, repeated tasks out of your way. Also see this question: C# Convert List to Dictionary ShareWebMar 14, 2013 · public static IEnumerable> Batch ( this IEnumerable source, int size) { T [] bucket = null; var count = 0; foreach (var item in source) { if (bucket == null) bucket = new T [size]; bucket [count++] = item; if (count != size) continue; yield return bucket.Select (x => x); bucket = null; count = 0; } // Return the last bucket with all remaining …WebApr 11, 2024 · The foreach statement: enumerates the elements of a collection and executes its body for each element of the collection. The do statement: conditionally executes its body one or more times. The while statement: conditionally executes its body zero or more times.WebApr 2, 2013 · foreach loop returns each element of a collection in the order it is called in the enumeration. foreach provides in order element access from a collection; it does not accept index and provides access to elements, so …WebApr 14, 2024 · string[] fruits = input.Split(delimiterChars, 3); foreach (string fruit in fruits) {. Console.WriteLine(fruit); } } } We use the Split method to split a string into an array of substrings based on an array of delimiter characters. We limit the number of substrings returned to 3 and output each element to the console.Web只有当我知道foreach中会发生一些需要时间或可能需要时间的重要事情时，我才使用并行foreach，比如数据库连接或向web服务发送大量数据。 如果它只是在服务器上处理信息，就像从已经加载到内存中的集合中获取ID一样，那么它真的不值得这样做。WebJun 8, 2024 · Sometimes, when looping over a collection of elements in C#, you need not only the items itself, but also its position in the collection. ... How to get the index of the current element in a foreach loop? The easiest way is to store and update the index in a separate variable. List< string > myFriends = new List< string > ...WebOct 31, 2008 · Example: if you use the LINQ extension method Reverse () on IEnumerable, which uses yield return to give the collection in reverse order, then doing a foreach (var myThing in myCollection.Reverse ()) will enumerate through the collection in reverse order. Important: yield return is key.WebWhen you say for-each in the context of C# List, there are two different ways, namely forEach statement and ForEach () method. forEach statement is a C# generic …WebSep 15, 2024 · C# int[] numbers = { 4, 5, 6, 1, 2, 3, -2, -1, 0 }; foreach (int i in numbers) { System.Console.Write (" {0} ", i); } // Output: 4 5 6 1 2 3 -2 -1 0 For multi-dimensional …WebSep 4, 2008 · The foreach is for iterating over collections that implement IEnumerable. It does this by calling GetEnumerator on the collection, which will return an Enumerator. This Enumerator has a method and a property: MoveNext () Current Current returns the object that Enumerator is currently on, MoveNext updates Current to the next object.WebFeb 28, 2024 · The Enum.The GetValues method returns an array of all enum values. The following code snippet loops through all values of an enum and prints them on the Console. foreach (int i in Enum.GetValues(typeof(Colors))) { Console.WriteLine($" {i}" ); } The Enum.The GetName method returns the constant's name in the specified enum with the …WebMar 24, 2009 · 4 Answers. Sorted by: 92. To enumerate a dictionary you either enumerate the values within it: Dictionary dic; foreach (string s in dic.Values) { Console.WriteLine (s); } or the KeyValuePairs. foreach (KeyValuePair kvp in dic) { Console.WriteLine ("Key : " + kvp.Key.ToString () + ", Value : " + kvp.Value); } or …WebLINQ doesn't have a ForEach method, and for good reason. LINQ is for performing queries.It is designed to get information from some data source. It is not designed to mutate data sources. LINQ queries shouldn't cause side …WebI'm trying to determine how to access the data that is in my JObject and I can't for the life of me determine how to use it. JObject Object = (JObject)Response.Data["my_key"]; I can print it to theWebOct 9, 2008 · I have an enumeration as follows: public enum RoleType {Administrator, Collaborator,...} How can I loop through each item in the enumeration and use it's …WebMar 28, 2024 · 编写高质量c#代码的10个建议. 1、使用有意义且见名知义的变量名. 这个建议也是各个研发经理代码规范的要求之一，这个建议能让代码更清晰易读，因为有意义的变量名可以更好地表达代码的含义，让代码更易于维护和修改。WebJan 9, 2024 · In C#, iterators are called enumerators, and they come from the IEnumerator interface. Basically, this interface provides a MoveNext() method, which goes for the next …WebJun 14, 2024 · You can just foreach the List private IEnumerable UpdateQueries (MySqlConnection connection, List queries) { foreach (var query in queries) { MySqlCommand command = new MySqlCommand (); command.Connection = connection; command.CommandText = query; command.ExecuteNonQuery (); yield return query; } } …
WebDec 31, 2024 · int i = 0; foreach (var f in familyListss) { familyData.Add (i, f); i++; } With a small extension method, you can build in an index to foreach to make it one line. Extension methods are worth exploring, and can take annoying, repeated tasks out of your way. Also see this question: C# Convert List to Dictionary Share
WebApr 14, 2024 · string[] fruits = input.Split(delimiterChars, 3); foreach (string fruit in fruits) {. Console.WriteLine(fruit); } } } We use the Split method to split a string into an array of substrings based on an array of delimiter characters. We limit the number of substrings returned to 3 and output each element to the console. scabies hot tub chlorineWebApr 10, 2024 · To iterate over this array using “foreach”, we can use the following code: foreach (int number in numbers) { Console.WriteLine (number); } In the above code, we are iterating over the ... scabies householdhttp://duoduokou.com/csharp/50737200094292871308.html scabies homoeopathic remediesWebJun 14, 2024 · You can just foreach the List private IEnumerable UpdateQueries (MySqlConnection connection, List queries) { foreach (var query in queries) { MySqlCommand command = new MySqlCommand (); command.Connection = connection; command.CommandText = query; command.ExecuteNonQuery (); yield return query; } } … scabies household contactsWebvar nameList = new List(); foreach (user in users) {nameList.Add(user.Name);} return nameList; With a LINQ query, you can extremely shorten the required code to this: return users.Select(u => u.Name).ToList(); Once you understand and can utilize LINQ queries, I guarantee you, that your code will gain much more readability. scabies house sprayWebFeb 1, 2012 · 103. LINQ doesn't help here, but you can use List.ForEach: List.ForEach Method. Performs the specified action on each element of the List. Example: myList.ForEach (p => myFunc (p)); The value passed to the lambda expression is the list item, so in this example p is a long if myList is a List. Share. Improve this … scabies how contagiousWebSep 20, 2024 · Use an index counter with C#’s foreach loop: here’s how Option 1: Create and manage an integer loop variable yourself Option 2: Use a tuple to get the foreach loop’s value and index Option 3: Replace foreach with the for statement Summary # Use an index counter with C#’s foreach loop: here’s how scabies how does it start