I have written code in C# which is exceeding page width, so I want it to be broken into next line according to my formatting. I tried to search a lot to get that character for line break but was not able to find out.
In VB.NET I use '_' for line break, same way what is used in C#?
I am trying to break a string.
In C# there's no 'new line' character like there is in VB.NET. The end of a logical 'line' of code is denoted by a ';'. If you wish to break the line of code over multiple lines, just hit the carriage return (or if you want to programmatically add it (for programmatically generated code) insert 'Environment.NewLine' or '\r\n'.
Edit: In response to your comment: If you wish to break a string over multiple lines (i.e. programmatically), you should insert the Environment.NewLine character. This will take the environment into account in order to create the line ending. For instance, many environments, including Unix/Linux only use a NewLine character (\n), but Windows uses both carriage return and line feed (\r\n). So to break a string you would use:
string output = "Hello this is my string\r\nthat I want broken over multiple lines."
Of course, this would only be good for Windows, so before I get flamed for incorrect practice you should actually do this:
string output = string.Format("Hello this is my string{0}that I want broken over multiple lines.", Environment.NewLine);
Or if you want to break over multiple lines in your IDE, you would do:
string output = "My string"
+ "is split over"
+ "multiple lines";
Option A: concatenate several string literal into one:
string myText = "Looking up into the night sky is looking into infinity" +
" - distance is incomprehensible and therefore meaningless.";
Option B: use a single multiline string literal:
string myText = #"Looking up into the night sky is looking into infinity
- distance is incomprehensible and therefore meaningless.";
With option B, the newline character(s) will be part of the string saved into variable myText. This might, or might not, be what you want.
result = "Minimum MarketData"+ Environment.NewLine
+ "Refresh interval is 1";
Use # symbol before starting the string.
like
string s = #"this is a really
long string
and this is
the rest of it";
If I am understanding this correctly, you should be able to break the string into substrings to accomplish this.
i.e.:
string s = "this is a really long string" +
"and this is the rest of it";
C# doesn't have an explicit line break character. You statements end with a semicolon so you can span your statements over many lines. These are both the same:
public string GenerateString()
{
return "abc" + "def";
}
public string GenerateString()
{
return
"abc" +
"def";
}
All you need to do is add \n or to write on files go \r\n.
Examples:
say you wanted to write duck(line break) cow this is how you would do it
Console.WriteLine("duck\n cow");
Edit: I think I didn't understand the question. You can use
#"duck
cow".Replace("\r\n", "")
as a linebreak in code, that produces \r\n which is used Windows.
C# code can be split between lines on pretty much any syntatic construct without a need for a '_' style construct.
For example
foo.
Bar(
42
, "again");
dt = abj.getDataTable(
"select bookrecord.userid,usermaster.userName, "
+" book.bookname,bookrecord.fromdate, "
+" bookrecord.todate,bookrecord.bookstatus "
+" from book,bookrecord,usermaster "
+" where bookrecord.bookid='"+ bookId +"' "
+" and usermaster.userId=bookrecord.userid "
+" and book.bookid='"+ bookId +"'");
guys.. use resources for long strings in code behind!!
also.. you don't need an _ for codeline breaks in C#. In VB the codelines end with a newline character (or a ':'), using the the _ would tell the parser it has not reached the end of the line yet. The codeline in C# ends with a ';' so you can use newlines to styleformat your code.
Strings are immutable, so using
public string GenerateString()
{
return
"abc" +
"def";
}
will slow you performance - each of those values is a string literal which must be concatenated at runtime - bad news if you reuse the method/property/whatever alot...
Store your string literals in resources is a good idea...
public string GenerateString()
{
return Resources.MyString;
}
That way it is localisable and the code is tidy (although performance is pretty terrible).
Related
I can't find how to split a Console.WriteLine text without creating a new line in the program. I mean, my code line is too long and it's uncomforable to scroll horizontally in order to check it
Console.WriteLine("BlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBla")
the result is only a line of text in the console (Might be split because of its length, but keeps being the same line)
into the same, but in different lines in the code, giving the same result. I've tried just splitting them with a new code of line as if it was common code like this:
Console.WriteLine("BlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBla
BlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBla
BlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBla
BlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBla")
and the result keeps being a line of text in the console
But looks like it's not the right way.
Sorry if it's stupid. Thanks
There's not a way to split a string literal in C# without embedding the line breaks in the string. The typical way to split a line like that is:
Console.WriteLine("BlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBla" +
"BlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBla" +
"BlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBla" +
"BlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBla");
If your string has line breaks, then you can use the literal string identifier #:
Console.WriteLine(#"This is one line followed by a carriage return
this is the second line of the string
and this is the third line");
You can use Console.Write instead and call it multiple times. Call WriteLine once at the end either as a part of the all or with an empty string to ensure you start on a new line when you are done with that string.
Console.Write("BlaBlaBlaBlaBlaBlaBlaBla");
Console.Write("BlaBlaBlaBlaBlaBlaBlaBla");
Console.Write("BlaBlaBlaBlaBlaBlaBlaBla");
Console.Write("BlaBlaBlaBlaBlaBlaBlaBla");
Console.WriteLine("BlaBlaBlaBlaBlaBlaBlaBla");
Console.WriteLine("BlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBla" +
"BlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBla" +
"BlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBla" +
"BlaBla");
If you have Resharper installed hitting enter inside of a string will automatically format the new line and add the + for you.
The best you can do is split long string into substrings and concat them before output:
Console.WriteLine("BlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBla"
+ "BlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBlaBla"
+ "BlaBlaBlaBlaBlaBlaBlaBlaBla")
If you only are going to write Bla then do
for(int i = 0; i < /*Amount of Bla's here*/; i++){
Console.Write("Bla");
}
I'm exporting text to a file in C# using System.IO.File.AppendAllText, and passing in the text file, and then the text I want to export with \n added to the end. When I view the text document, they are not on different lines, although that pesky return-line character is there between the lines. So the system may think it's two line, but a user sees it as one. How can this be fixed automatically without doing a find-replace every time I generate a file?
System.IO.File.AppendAllText(#"./WarningsLog.txt", line + "\n");
You need to use the Environment.NewLine instead of \n, because newline can be more than that. in windows (if I'm not mistaken), the default is actually \r\n
Although, using \r\n, will help you temporary, using Environment.NewLine is the proper way to go
First off, there are a couple of ways to represent the new line.
The most commonly used are:
The unix way - to write the \n character. \n here represents the newline character.
The windows way - to write the \r\n characters. \r here goes for the carriage return character.
If you are writing something platform-independent, Environment.NewLine will do the job for you and pick the correct character(s).
MSDN states it represents:
A string containing "\r\n" for non-Unix platforms, or a string containing "\n" for Unix platforms.
Also, in some cases you may want to use System.IO.File.AppendAllLines that takes an IEnumerable<string> as the lines collection and appends it to the file. It uses Environment.NewLine inside.
You could try building this with some file specific characters checks , like
new line, tab , etc....
Here is an example code which checks for new line and tabs :
public static string Replace()
{
string rLower = words.ToLower().Replace(Environment.NewLine, "<replaced_newLine>");
rLower = rLower.Replace("\t", "<replaced_Tabulation>");
return rLower;
}
Of course you might have a lot of different combinations , where an item that needs to be changed is followed by " " or "\n" or "\r\n" or "\t"
Is there an easy way to create a multiline string literal in C#?
Here's what I have now:
string query = "SELECT foo, bar"
+ " FROM table"
+ " WHERE id = 42";
I know PHP has
<<<BLOCK
BLOCK;
Does C# have something similar?
You can use the # symbol in front of a string to form a verbatim string literal:
string query = #"SELECT foo, bar
FROM table
WHERE id = 42";
You also do not have to escape special characters when you use this method, except for double quotes as shown in Jon Skeet's answer.
It's called a verbatim string literal in C#, and it's just a matter of putting # before the literal. Not only does this allow multiple lines, but it also turns off escaping. So for example you can do:
string query = #"SELECT foo, bar
FROM table
WHERE name = 'a\b'";
This includes the line breaks (using whatever line break your source has them as) into the string, however. For SQL, that's not only harmless but probably improves the readability anywhere you see the string - but in other places it may not be required, in which case you'd either need to not use a multi-line verbatim string literal to start with, or remove them from the resulting string.
The only bit of escaping is that if you want a double quote, you have to add an extra double quote symbol:
string quote = #"Jon said, ""This will work,"" - and it did!";
As a side-note, with C# 6.0 you can now combine interpolated strings with the verbatim string literal:
string camlCondition = $#"
<Where>
<Contains>
<FieldRef Name='Resource'/>
<Value Type='Text'>{(string)parameter}</Value>
</Contains>
</Where>";
The problem with using string literal I find is that it can make your code look a bit "weird" because in order to not get spaces in the string itself, it has to be completely left aligned:
var someString = #"The
quick
brown
fox...";
Yuck.
So the solution I like to use, which keeps everything nicely aligned with the rest of your code is:
var someString = String.Join(
Environment.NewLine,
"The",
"quick",
"brown",
"fox...");
And of course, if you just want to logically split up lines of an SQL statement like you are and don't actually need a new line, you can always just substitute Environment.NewLine for " ".
One other gotcha to watch for is the use of string literals in string.Format. In that case you need to escape curly braces/brackets '{' and '}'.
// this would give a format exception
string.Format(#"<script> function test(x)
{ return x * {0} } </script>", aMagicValue)
// this contrived example would work
string.Format(#"<script> function test(x)
{{ return x * {0} }} </script>", aMagicValue)
Why do people keep confusing strings with string literals? The accepted answer is a great answer to a different question; not to this one.
I know this is an old topic, but I came here with possibly the same question as the OP, and it is frustrating to see how people keep misreading it. Or maybe I am misreading it, I don't know.
Roughly speaking, a string is a region of computer memory that, during the execution of a program, contains a sequence of bytes that can be mapped to text characters. A string literal, on the other hand, is a piece of source code, not yet compiled, that represents the value used to initialize a string later on, during the execution of the program in which it appears.
In C#, the statement...
string query = "SELECT foo, bar"
+ " FROM table"
+ " WHERE id = 42";
... does not produce a three-line string but a one liner; the concatenation of three strings (each initialized from a different literal) none of which contains a new-line modifier.
What the OP seems to be asking -at least what I would be asking with those words- is not how to introduce, in the compiled string, line breaks that mimick those found in the source code, but how to break up for clarity a long, single line of text in the source code without introducing breaks in the compiled string. And without requiring an extended execution time, spent joining the multiple substrings coming from the source code. Like the trailing backslashes within a multiline string literal in javascript or C++.
Suggesting the use of verbatim strings, nevermind StringBuilders, String.Joins or even nested functions with string reversals and what not, makes me think that people are not really understanding the question. Or maybe I do not understand it.
As far as I know, C# does not (at least in the paleolithic version I am still using, from the previous decade) have a feature to cleanly produce multiline string literals that can be resolved during compilation rather than execution.
Maybe current versions do support it, but I thought I'd share the difference I perceive between strings and string literals.
UPDATE:
(From MeowCat2012's comment) You can. The "+" approach by OP is the best. According to spec the optimization is guaranteed: http://stackoverflow.com/a/288802/9399618
Add multiple lines : use #
string query = #"SELECT foo, bar
FROM table
WHERE id = 42";
Add String Values to the middle : use $
string text ="beer";
string query = $"SELECT foo {text} bar ";
Multiple line string Add Values to the middle: use $#
string text ="Customer";
string query = $#"SELECT foo, bar
FROM {text}Table
WHERE id = 42";
You can use # and "".
string sourse = #"{
""items"":[
{
""itemId"":0,
""name"":""item0""
},
{
""itemId"":1,
""name"":""item1""
}
]
}";
In C# 11 [2022], you will be able to use Raw String literals.
The use of Raw String Literals makes it easier to use " characters without having to write escape sequences.
Solution for OP:
string query1 = """
SELECT foo, bar
FROM table
WHERE id = 42
""";
string query2 = """
SELECT foo, bar
FROM table
WHERE id = 42
and name = 'zoo'
and type = 'oversized "jumbo" grand'
""";
More details about Raw String Literals
See the Raw String Literals GitHub Issue for full details; and Blog article C# 11 Preview Updates – Raw string literals, UTF-8 and more!
I haven't seen this, so I will post it here (if you are interested in passing a string you can do this as well.) The idea is that you can break the string up on multiple lines and add your own content (also on multiple lines) in any way you wish. Here "tableName" can be passed into the string.
private string createTableQuery = "";
void createTable(string tableName)
{
createTableQuery = #"CREATE TABLE IF NOT EXISTS
["+ tableName + #"] (
[ID] INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT,
[Key] NVARCHAR(2048) NULL,
[Value] VARCHAR(2048) NULL
)";
}
Yes, you can split a string out onto multiple lines without introducing newlines into the actual string, but it aint pretty:
string s = $#"This string{
string.Empty} contains no newlines{
string.Empty} even though it is spread onto{
string.Empty} multiple lines.";
The trick is to introduce code that evaluates to empty, and that code may contain newlines without affecting the output. I adapted this approach from this answer to a similar question.
There is apparently some confusion as to what the question is, but there are two hints that what we want here is a string literal not containing any newline characters, whose definition spans multiple lines. (in the comments he says so, and "here's what I have" shows code that does not create a string with newlines in it)
This unit test shows the intent:
[TestMethod]
public void StringLiteralDoesNotContainSpaces()
{
string query = "hi"
+ "there";
Assert.AreEqual("hithere", query);
}
Change the above definition of query so that it is one string literal, instead of the concatenation of two string literals which may or may not be optimized into one by the compiler.
The C++ approach would be to end each line with a backslash, causing the newline character to be escaped and not appear in the output. Unfortunately, there is still then the issue that each line after the first must be left aligned in order to not add additional whitespace to the result.
There is only one option that does not rely on compiler optimizations that might not happen, which is to put your definition on one line. If you want to rely on compiler optimizations, the + you already have is great; you don't have to left-align the string, you don't get newlines in the result, and it's just one operation, no function calls, to expect optimization on.
If you don't want spaces/newlines, string addition seems to work:
var myString = String.Format(
"hello " +
"world" +
" i am {0}" +
" and I like {1}.",
animalType,
animalPreferenceType
);
// hello world i am a pony and I like other ponies.
You can run the above here if you like.
using System;
namespace Demo {
class Program {
static void Main(string[] args) {
string str = #"Welcome User,
Kindly wait for the image to
load";
Console.WriteLine(str);
}
}
}
Output
Welcome User,
Kindly wait for the image to
load
Short question: I have a string in my resources: "This is my test string {0}\n\nTest"
I'm trying to display this string in my Messagebox:
MessageBox.Show(String.Format(Properties.Resources.About,
Constants.VERSION),
Properties.Resources.About_Title, MessageBoxButton.OK,
MessageBoxImage.Information);
However I don't get new lines. The \n still show up as characters, not as new lines.
I also tried to use a workaround like mystring.Replace("\n", Environment.NewLine) but this also doesn't change anything.
What am I doing wrong?
Edit: Funny thing to mention: Replace("\n", "somethingelse") doesn't change anything.
Edit2: Shift+Enter in my Resource-File instead of \n seems to work... Strange behaviour anyway
Put a place holder where you want to put new line and in the code where you use that resource string, just replace it with new line: string resource: "This is first line.{0}This is second line.{0}This is third line." You will use this resource string like this: MessageBox.Show(string.Format(MyStringResourceClass.MyStringPropertyName, Environment.NewLine));
OR
Unconventional Method
But i just now got it working by coping newline from word directly (or anyother place) & pasting it inside the resource string file.
It was simple..
OR
\r\n characters will be converted to new line when you display it by using message box or assign it to text box or whenever you use it in interface.
In C# (like most C derived languages), escape characters are used to denote special characters such as return and tab, and + is used in place of & for string concatenation.
To make your code work under C# you’ve got two options... the first is to simply replace the NewLine with the return escape character \n ala:
MessageBox.Show("this is first line" + "\n" + "this is second line");
The other method, and more correct is to replace it instead with Environment.NewLine which theoretically could change depending on the system you are using (however unlikely).
MessageBox.Show("this is first line" + Environment.NewLine + "this is second line");
In the resource editor seperate your string content by using shift+enter. Or else, edit your ResX file in xml editor and using enter key create a new line for your resource string.
Refer this link for detail info: Carriage Return/Line in ResX file.
Try this:
String outputMessage = string.Format("Line 1{0}Line 2{0}Line 3", Environment.NewLine);
MessageBox.Show(outputMessage);
A further example with another variable:
String anotherValue = "Line 4";
String outputMessage = string.Format("Line 1{0}Line 2{0}Line 3{0}{1}", Environment.NewLine, anotherValue);
MessageBox.Show(outputMessage);
Try this
removing the MessageBoxButtons.OK and MessageBoxImage. Information.
MessageBox.Show(String.Format(Properties.Resources.About,
Constants.VERSION),
Properties.Resources.About_Title);
What I have is a C# windows app that reads a bunch of SQL tables and creates a bunch of queries based on the results. What I'm having a small issue with is the final "," on my query
This is what I have
ColumnX,
from
I need to read the entire file, write out exactly what is in the file and just replace the last , before the from with nothing.
I tried .replace(#",\n\nfrom),(#"\n\nfrom) but it's not finding it. Any help is appreciated.
Example:
ColumnX,
from
Result:
ColumnX
from
The line break is most likely the two character combination CR + LF:
.replace(",\r\n\r\nfrom","\r\n\r\nfrom")
If you want the line break for the current system, you can use the Environment.NewLine constant:
.replace(","+Environment.NewLine+Environment.NewLine+"from",Environment.NewLine+Environment.NewLine+"from")
Note that the # in front of a string means that it doesn't use backslash escape sequences, but on the other hand it can contain line breaks, so you could write it in this somewhat confusing way:
str = str.replace(#",
from", #"
from");
There are two solutions that you can try:
Remove the # symbol, as that means it's going to look for the literal characters of \n rather than a newline.
Try .replace("," + Environment.NewLine + Environment.NewLine + from, Environment.NewLine + Environment.NewLine + "from)
Instead of replacing or removing the comma when you read the file, it would probably be preferable to remove it before the file is written. That way you only have to bother with the logic once. As you are building your column list, just remove the last comma after the list is created. Hopefully you are in a position where you have control over that process.
If you can assume you always want to remove the last occurrence of the comma you can use the string function LastIndexOf to find the index for the last comma and use Remove from there.
myString = myString.Remove(myString.LastIndexOf(","), 1);
What about using Regex? Does that handle different forms of linefeed better?
var result = Regex.Replace(input, #",(\n*)from", "$1from");