C中的换行符#

C允许在多行上拆分字符串,该术语称为 verbatim literal :

string myString = @"this is a
                    test
                   to see how long my string
                   can be



                    and it can be quite long";

如果你正在寻找替代 & _ 从vb,使用 + 加入你的行列。

字符串恒量

只使用 + 运算符,并将字符串分解为人类可读的行。编译器会发现字符串是常量,并在编译时将它们连接起来。请参阅msdn c编程指南 here .

例如

const string myVeryLongString = 
    "This is the opening paragraph of my long string. " +
    "Which is split over multiple lines to improve code readability, " +
    "but is in fact, just one long string.";

IL_0003: ldstr "This is the opening paragraph of my long string. Which is split over multiple lines to improve code readability, but is in fact, just one long string."

字符串变量

注意,当使用字符串插值将值替换为字符串时, $ 字符必须在前面 每个 需要替换的行:

var interpolatedString = 
    "This line has no substitutions. " +
    $" This line uses {count} widgets, and " +
    $" {CountFoos()} foos were found.";

然而,这有 负业绩 多次调用的结果 string.Format 以及字符串的最终连接(标记为 *** )

IL_002E:  ldstr       "This line has no substitutions. "
IL_0033:  ldstr       " This line uses {0} widgets, and "
IL_0038:  ldloc.0     // count
IL_0039:  box         System.Int32
IL_003E:  call        System.String.Format ***
IL_0043:  ldstr       " {0} foos were found."
IL_0048:  ldloc.1     // CountFoos
IL_0049:  callvirt    System.Func<System.Int32>.Invoke
IL_004E:  box         System.Int32
IL_0053:  call        System.String.Format ***
IL_0058:  call        System.String.Concat ***

尽管你可以使用 $@ 为了提供单个字符串并避免性能问题, unless the whitespace is placed inside {} (这看起来很奇怪,IMO),这和尼尔·奈特的答案有着相同的问题,因为它将包括任何行分解中的空白:

var interpolatedString = $@"When breaking up strings with `@` it introduces
    <- [newLine and whitespace here!] each time I break the string.
    <- [More whitespace] {CountFoos()} foos were found.";

注入的空白很容易被发现:

IL_002E:  ldstr       "When breaking up strings with `@` it introduces
    <- [newLine and whitespace here!] each time I break the string.
    <- [More whitespace] {0} foos were found."

另一种选择是回到 字符串格式 . 这里,根据我的初始答案,格式化字符串是一个常量:

const string longFormatString = 
    "This is the opening paragraph of my long string with {0} chars. " +
    "Which is split over multiple lines to improve code readability, " +
    "but is in fact, just one long string with {1} widgets.";

然后评估如下:

string.Format(longFormatString, longFormatString.Length, CountWidgets());

但是,考虑到格式化字符串和替换标记之间可能存在分离,这仍然很难维护。

@"string here
that is long you mean"

但是要小心,因为

@"string here
           and space before this text
     means the space is also a part of the string"

它也会避开字符串中的内容

@"c:\\folder" // c:\\folder
@"c:\folder" // c:\folder
"c:\\folder" // c:\folder

相关的

• What does the @ symbol before a variable name mean in C#?
• MSDN string reference

您可以使用逐字文字:

const string test = @"Test
123
456
";

但第1行的凹痕很难看。

您必须使用以下方法之一:

    string s = @"loooooooooooooooooooooooong loooooong
                  long long long";

string s = "loooooooooong loooong" +
           " long long" ;

如果声明了不同的变量,则使用以下简单方法:

Int salary=2000;

String abc="I Love Pakistan";

Double pi=3.14;

Console.Writeline=salary+"/n"+abc+"/n"+pi;
Console.readkey();