Trim c что это

Конкатенация строк или объединение может производиться как с помощью операции + , так и с помощью метода Concat :

Метод Concat является статическим методом класса string, принимающим в качестве параметров две строки. Также имеются другие версии метода, принимающие другое количество параметров.

Для объединения строк также может использоваться метод Join :

Метод Join также является статическим. Использованная выше версия метода получает два параметра: строку-разделитель (в данном случае пробел) и массив строк, которые будут соединяться и разделяться разделителем.

Сравнение строк

Для сравнения строк применяется статический метод Compare :

Данная версия метода Compare принимает две строки и возвращает число. Если первая строка по алфавиту стоит выше второй, то возвращается число меньше нуля. В противном случае возвращается число больше нуля. И третий случай — если строки равны, то возвращается число 0.

В данном случае так как символ h по алфавиту стоит выше символа w, то и первая строка будет стоять выше.

Поиск в строке

С помощью метода IndexOf мы можем определить индекс первого вхождения отдельного символа или подстроки в строке:

Подобным образом действует метод LastIndexOf , только находит индекс последнего вхождения символа или подстроки в строку.

Еще одна группа методов позволяет узнать начинается или заканчивается ли строка на определенную подстроку. Для этого предназначены методы StartsWith и EndsWith . Например, в массиве строк хранится список файлов, и нам надо вывести все файлы с расширением exe:

Разделение строк

С помощью функции Split мы можем разделить строку на массив подстрок. В качестве параметра функция Split принимает массив символов или строк, которые и будут служить разделителями. Например, подсчитаем количество слов в сроке, разделив ее по пробельным символам:

Это не лучший способ разделения по пробелам, так как во входной строке у нас могло бы быть несколько подряд идущих пробелов и в итоговый массив также бы попадали пробелы, поэтому лучше использовать другую версию метода:

Второй параметр StringSplitOptions.RemoveEmptyEntries говорит, что надо удалить все пустые подстроки.

Обрезка строки

Для обрезки начальных или концевых символов используется функция Trim :

Функция Trim без параметров обрезает начальные и конечные пробелы и возвращает обрезанную строку. Чтобы явным образом указать, какие начальные и конечные символы следует обрезать, мы можем передать в функцию массив этих символов.

Эта функция имеет частичные аналоги: функция TrimStart обрезает начальные символы, а функция TrimEnd обрезает конечные символы.

Обрезать определенную часть строки позволяет функция Substring :

Функция Substring также возвращает обрезанную строку. В качестве параметра первая использованная версия применяет индекс, начиная с которого надо обрезать строку. Вторая версия применяет два параметра — индекс начала обрезки и длину вырезаемой части строки.

Вставка

Для вставки одной строки в другую применяется функция Insert :

Первым параметром в функции Insert является индекс, по которому надо вставлять подстроку, а второй параметр — собственно подстрока.

Удаление строк

Удалить часть строки помогает метод Remove :

Первая версия метода Remove принимает индекс в строке, начиная с которого надо удалить все символы. Вторая версия принимает еще один параметр — сколько символов надо удалить.

Замена

Чтобы заменить один символ или подстроку на другую, применяется метод Replace :

Во втором случае применения функции Replace строка из одного символа «о» заменяется на пустую строку, то есть фактически удаляется из текста. Подобным способом легко удалять какой-то определенный текст в строках.

Смена регистра

Для приведения строки к верхнему и нижнему регистру используются соответственно функции ToUpper() и ToLower() :

How to remove all white space from the beginning or end of a string?

How can I remove all white space from the beginning and end of a string?

«hello» returns «hello»
«hello » returns «hello»
» hello » returns «hello»
» hello world » returns «hello world»

7 Answers 7

String.Trim() returns a string which equals the input string with all white-spaces trimmed from start and end:

String.TrimStart() returns a string with white-spaces trimmed from the start:

String.TrimEnd() returns a string with white-spaces trimmed from the end:

None of the methods modify the original string object.

(In some implementations at least, if there are no white-spaces to be trimmed, you get back the same string object you started with:

C# | Trim() Method

C# Trim() is a string method. This method is used to removes all leading and trailing white-space characters from the current String object. This method can be overloaded by passing arguments to it.

Syntax:

Explanation : First method will not take any parameter and the second method will take an array of Unicode characters or null as a parameter. Null is because of params keyword. The type of Trim() method is System.String.

Note: If no parameter is pass in public string Trim() then Null , TAB, Carriage Return and White Space will automatically remove if they are present in current string object. And If any parameter will pass into the Trim() method then only specified character(which passed as arguments in Trim() method) will be removed from the current string object. Null, TAB, Carriage Return, and White Space will not remove automatically if they are not specified in the arguments list.

Below are the programs to demonstrate the above method :

Example 1:

public string Trim()

C# Trim Function: Streamline Your Code

This article explores the C# Trim function and its usage in string manipulation tasks. We cover its basic syntax, removing white space, removing specific characters, combining with other functions, performance considerations, alternatives, and real-world examples. Plus, a code joke at the end!

If you’re tired of dealing with unnecessary white space in your C# code, the Trim function is here to help. This simple yet powerful tool can help you streamline your code and improve its readability, making it easier to work with and maintain over time. In this article, we’ll explore the ins and outs of C# Trim, from its basic syntax to more advanced usage scenarios. Whether you’re a seasoned pro or just getting started with C#, you won’t want to miss this essential guide to one of the language’s most useful functions.

Important disclosure: we’re proud affiliates of some tools mentioned in this guide. If you click an affiliate link and subsequently make a purchase, we will earn a small commission at no additional cost to you (you pay nothing extra). For more information, read our affiliate disclosure.

Introduction To C# Trim And Its Basic Syntax

The Trim function in C# is used to remove white space and other specified characters from the beginning and/or end of a string.
The basic syntax for using Trim is: string.Trim() , which removes all leading and trailing white space from the string.
Other variants of the Trim function include TrimStart and TrimEnd, which only remove leading or trailing white space, respectively.
The Trim function is a part of the System.String class in C#.

Example:

This example uses the basic Trim function to remove leading and trailing white space from the string » Hello, world! «, resulting in the trimmed string «Hello, world!».

Removing White Space From The Beginning And End Of A String Using Trim

The basic Trim function removes all leading and trailing white space from a string.
Leading white space refers to any whitespace characters at the beginning of the string, such as spaces or tabs.
Trailing white space refers to any whitespace characters at the end of the string.
The Trim function can be useful for cleaning up user input or formatting strings for display.

Example:

This example uses the Trim function to remove leading and trailing white space from the user input string » Hello! «, resulting in the cleaned string «Hello!». This can be useful for ensuring consistent formatting of user input, especially in scenarios where the user may accidentally include extra white space.

Using TrimStart And TrimEnd To Remove White Space From The Beginning Or End Of A String Only

TrimStart removes leading white space from a string, while TrimEnd removes trailing white space.
These functions can be useful if you only want to remove white space from one end of a string.
Both functions have variants that allow you to specify which characters to remove, in addition to white space.

Example:

In this example, the TrimStart function removes the leading white space from the string » Hello, world! «, resulting in the string «Hello, world! «. The TrimEnd function removes the trailing white space instead, resulting in the string » Hello, world!».

Removing Specific Characters From The Beginning Or End Of A String Using TrimStart And TrimEnd

In addition to white space, you can specify other characters to remove from the beginning or end of a string using the TrimStart and TrimEnd functions.
To do so, you pass an array of characters to remove as a parameter to the function.

Example:

In this example, we pass an array of characters to remove as a parameter to the TrimStart and TrimEnd functions, in addition to white space. The resulting trimmed strings remove the specified characters from either the beginning or end of the string.

Combining Trim With Other String Manipulation Functions To Perform More Complex Operations

Trim can be used in combination with other string manipulation functions to perform more complex operations.
For example, you can use Trim to remove leading or trailing white space from a string before performing a string comparison.
You can also use Trim to remove leading or trailing characters from a string before performing a substring operation.

Example:

In the first example, we use Trim to remove leading and trailing white space from the string » Hello, world! » before performing a case-insensitive string comparison to see if it contains the substring «world». In the second example, we use Trim to remove leading and trailing white space from a formatted full name string before extracting the last name using the Substring function.

Best Practices For Using Trim In Your Code

When using Trim, it’s important to consider the potential impact on performance, especially when working with large strings or in tight loops.
To minimize performance overhead, it’s generally best to use Trim only when necessary and to avoid using it on every string operation.
Additionally, it’s a good practice to be explicit about which characters you want to remove when using TrimStart and TrimEnd, rather than relying on the default behavior of removing all white space.

Example:

In the first example, we use Trim in a tight loop, which can be inefficient since it applies the function to every string in the array, even if the string doesn’t contain any white space. In the second example, we use Trim on a single string, which is more efficient since it only applies the function once. In the third example, we use TrimStart with an explicit list of characters to remove, rather than relying on the default behavior of removing all white space, which can make the code more clear and less error-prone.

Performance Considerations When Using Trim On Large Strings Or In Tight Loops

While Trim is a relatively simple function, it can still have an impact on performance when used on large strings or in tight loops.
In general, it’s best to avoid using Trim unnecessarily and to minimize its use as much as possible.
Additionally, it can be more performant to use manual string manipulation techniques, such as StringBuilder or string indexing, rather than relying on Trim in certain scenarios.

Example:

In the first example, we use Trim in a tight loop with a very large string, which can be very slow and memory-intensive. In the second example, we use manual string manipulation techniques, such as StringBuilder and string indexing, to remove white space from the string instead of using Trim, which can be faster and use less memory.

Alternatives To Trim, Such As Regex Or Manual String Manipulation, And When To Use Them Instead

While Trim is a useful function for removing white space and other characters from the beginning and/or end of a string, it’s not always the best solution for every scenario.
In some cases, regular expressions (Regex) can be more powerful and flexible than Trim for string manipulation tasks.
Additionally, manual string manipulation techniques, such as StringBuilder or string indexing, can be faster and more efficient than Trim in certain scenarios.

Example:

In the first example, we use Regex to remove all non-alphabetic characters from a string, which is more flexible than using Trim since we can specify exactly which characters we want to remove. In the second example, we use manual string manipulation techniques, such as Replace and Trim, to remove specific characters from the string, which can be more efficient than using Trim in certain scenarios.

Real-World Examples Of Trim Usage In C# Applications

Trim is a widely used function in C# and can be found in a variety of different types of applications.
For example, Trim can be used to clean up user input in a web application, remove unnecessary whitespace in a text editor, or format strings for display in a console application.
Additionally, Trim can be used in combination with other string manipulation functions to perform more complex operations, such as parsing data from a file or extracting information from a database.

Example:

In these examples, we can see a few different ways in which Trim might be used in a real-world C# application. In the first example, we use Trim to clean up user input in a web form before processing it further. In the second example, we use Trim to remove unnecessary whitespace from text entered into a text editor. In the third example, we use Trim to format a string for display in a console application. Finally, in the fourth example, we use Trim in combination with other string manipulation functions to parse data from a file.

Conclusion

Trim is a handy function in C# that can help you clean up your strings and get rid of unwanted whitespace. Whether you’re working on a web application, a text editor, or a console program, Trim can be a valuable tool in your toolkit.

But be careful not to overuse Trim, or you might find yourself in a tight loop! And remember, while Trim can be a useful function, sometimes it’s better to use other string manipulation techniques like StringBuilder or Regex for more complex tasks.

C# | Trim() Method

C# Trim() is a string method. This method is used to removes all leading and trailing white-space characters from the current String object. This method can be overloaded by passing arguments to it.

Syntax:

Below are the programs to demonstrate the above method :

Example 1:

public string Trim()

String Trim Functions In C (Remove Leading And Trailing Space)

Standard string library of c lacks trim(), ltrim() and rtrim() functions. If you have some basic knowledge of MySQL or PHP,surely you gonna miss them in C. But if know how to play with character arrays (i.e. strings) you can incarnate them in C. This C tutorial will explain you string trim functions in C.

What are string trim functions?

String trim functions are used to remove extra white-space from strings. These functions can remove white-space in string either from left side or from right side or both side.

Logic For String Trim Functions In C

Well trimming logic in C is not much difficult. We are going to follow these steps:-

Get input in main() using fgets function. After that, remove extra next line character (\n) using string library.
Create rtrim() and ltrim() which eliminate extra white-spaces and tabs (\t).
Call rtrim() and ltrim() functions and get desired results. Logic for rtrim() and ltrim() is mentioned below.

#1 Rtrim() logic in C

Rtrim function removes all leading spaces from input string (i.e. remove white-space from string on right side).

For rtrim function, we start reading characters of string from right side. If character is blank space then replace it by terminating zero (‘\0’). Keep repeating this till find a non blank space character.

In this way all spaces get removed by ‘\0’ and left most ‘\0’ becomes last character of string array. Thus all trailing spaces get eliminated.

#2 Ltrim() logic in C

Ltrim function removes all trailing spaces from input string str2 (i.e. remove white-space from string on left side).

For ltrim function, start scanning characters from left side. Keep skipping till position of first non space character. Store trimmed part of input string in new string ltrim. Thus all leading space removed and manipulated string stored in ltrim.

#3 Trim() logic in c

Trim function removes all leading and trailing spaces. We can combine logic of ltrim() and rtrim() inside trim function.

Remove leading and trailing blank space in C using while loop.

Minimize Size Of Trim()

In above program we successfully removed extra blank space characters from both left and right. We can improve above logic by declaring functions as character pointer instead of void.

It will help to reduce size of trim function.

In this way you can create simple string trim functions in C. Feel free to ask your doubts in comments.

What is Trim() method in C#?

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The Trim() method in C# is used to remove any leading and trailing whitespace characters in a string. This means that it removes any whitespace that begins or ends a string.

Syntax

Parameters

Return value

It returns a string that contains no whitespace.

Code example

In the code example below, we will create some strings with whitespaces and remove those that start or ends them.

How to remove all white space from the beginning or end of a string?

How can I remove all white space from the beginning and end of a string?

«hello» returns «hello»
«hello » returns «hello»
» hello » returns «hello»
» hello world » returns «hello world»

7 Answers 7

String.Trim() returns a string which equals the input string with all white-spaces trimmed from start and end:

String.TrimStart() returns a string with white-spaces trimmed from the start:

String.TrimEnd() returns a string with white-spaces trimmed from the end:

None of the methods modify the original string object.

(In some implementations at least, if there are no white-spaces to be trimmed, you get back the same string object you started with:

Trim c что это