문자열과 관련된 다양한 작업
방법: 문자열 내에서 검색
string searchWithinThis = "ABCDEFGHIJKLMNOP";
string searchForThis = "DEF";
int firstCharacter = searchWithinThis.IndexOf(searchForThis);
System.Console.WriteLine("First occurrence: {0}", firstCharacter);
방법: 문자열 배열에서 문자열 검색
string[] strArray = {"ABCDEFG", "HIJKLMNOP"};
string findThisString = "JKL";
int strNumber;
int strIndex = 0;
for (strNumber = 0; strNumber < strArray.Length; strNumber++)
{
strIndex = strArray[strNumber].IndexOf(findThisString);
if (strIndex >= 0)
break;
}
System.Console.WriteLine("String number: {0}\nString index: {1}",
strNumber, strIndex);
이스케이프 문자
string columns = "Column 1\tColumn 2\tColumn 3";
//Output: Column 1 Column 2 Column 3
string rows = "Row 1\r\nRow 2\r\nRow 3";
/* Output:
Row 1
Row 2
Row 3
*/
string title = "\"The \u00C6olean Harp\", by Samuel Taylor Coleridge";
//Output: "The Æolean Harp", by Samuel Taylor Coleridge
@ 기호
string p1 = "\\\\My Documents\\My Files\\";
string p2 = @"\\My Documents\My Files\";
ToString()
int year = 1999;
string msg = "Eve was born in " + year.ToString();
System.Console.WriteLine(msg); // outputs "Eve was born in 1999"
개별 문자 액세스
string s3 = "Visual C# Express";
System.Console.WriteLine(s3.Substring(7, 2));
// Output: "C#"
System.Console.WriteLine(s3.Replace("C#", "Basic"));
// Output: "Visual Basic Express"
// Index values are zero-based
int index = s3.IndexOf("C");
// index = 7
----------------------------------------------------------------------------
string question = "hOW DOES mICROSOFT wORD DEAL WITH THE cAPS lOCK KEY?";
System.Text.StringBuilder sb = new System.Text.StringBuilder(question);
for (int j = 0; j < sb.Length; j++)
{
if (System.Char.IsLower(sb[j]) == true)
sb[j] = System.Char.ToUpper(sb[j]);
else if (System.Char.IsUpper(sb[j]) == true)
sb[j] = System.Char.ToLower(sb[j]);
}
// Store the new string.
string corrected = sb.ToString();
System.Console.WriteLine(corrected);
// Output: How does Microsoft Word deal with the Caps Lock key?
----------------------------------------------------------------------------
string s5 = "Printing backwards";
for (int i = 0; i < s5.Length; i++)
{
System.Console.Write(s5[s5.Length - i - 1]);
}
// Output: "sdrawkcab gnitnirP"
대/소문자 바꾸기
string s6 = "Battle of Hastings, 1066";
System.Console.WriteLine(s6.ToUpper());
// outputs "BATTLE OF HASTINGS 1066"
System.Console.WriteLine(s6.ToLower());
// outputs "battle of hastings 1066"
비교
// Internal strings that will never be localized.
string root = @"C:\users";
string root2 = @"C:\Users";
// Use the overload of the Equals method that specifies a StringComparison.
// Ordinal is the fastest way to compare two strings.
bool result = root.Equals(root2, StringComparison.Ordinal);
Console.WriteLine("Ordinal comparison: {0} and {1} are {2}", root, root2,
result ? "equal." : "not equal.");
// To ignore case means "user" equals "User". This is the same as using
// String.ToUpperInvariant on each string and then performing an ordinal comparison.
result = root.Equals(root2, StringComparison.OrdinalIgnoreCase);
Console.WriteLine("Ordinal ignore case: {0} and {1} are {2}", root, root2,
result ? "equal." : "not equal.");
// A static method is also available.
bool areEqual = String.Equals(root, root2, StringComparison.Ordinal);
// String interning. Are these really two distinct objects?
string a = "The computer ate my source code.";
string b = "The computer ate my source code.";
// ReferenceEquals returns true if both objects
// point to the same location in memory.
if (String.ReferenceEquals(a, b))
Console.WriteLine("a and b are interned.");
else
Console.WriteLine("a and b are not interned.");
// Use String.Copy method to avoid interning.
string c = String.Copy(a);
if (String.ReferenceEquals(a, c))
Console.WriteLine("a and c are interned.");
else
Console.WriteLine("a and c are not interned.");
-------------------------------------------------------------------------
// Enter different values for string1 and string2 to
// experiement with behavior of CompareTo
string string1 = "ABC";
string string2 = "abc";
int result2 = string1.CompareTo(string2);
if (result2 > 0)
{
System.Console.WriteLine("{0} is greater than {1}", string1, string2);
}
else if (result2 == 0)
{
System.Console.WriteLine("{0} is equal to {1}", string1, string2);
}
else if (result2 < 0)
{
System.Console.WriteLine("{0} is less than {1}", string1, string2);
}
// Output: ABC is less than abc
---------------------------------------------------------------------------
// Date strings are interpreted according to the current culture.
// If the culture is en-US, this is interpreted as "January 8, 2008",
// but if the user's computer is fr-FR, this is interpreted as "August 1, 2008"
string date = "01/08/2008";
DateTime dt = Convert.ToDateTime(date);
Console.WriteLine("Year: {0}, Month: {1}, Day: {2}", dt.Year, dt.Month, dt.Day);
// Specify exactly how to interpret the string.
IFormatProvider culture = new System.Globalization.CultureInfo("fr-FR", true);
// Alternate choice: If the string has been input by an end user, you might
// want to format it according to the current culture:
// IFormatProvider culture = System.Threading.Thread.CurrentThread.CurrentCulture;
DateTime dt2 = DateTime.Parse(date, culture, System.Globalization.DateTimeStyles.AssumeLocal);
Console.WriteLine("Year: {0}, Month: {1}, Day {2}", dt2.Year, dt2.Month, dt2.Day);
/* Output (assuming first culture is en-US and second is fr-FR):
Year: 2008, Month: 1, Day: 8
Year: 2008, Month: 8, Day 1
*/
문자열을 부분 문자열로 분할
string numString = "1287543"; //"1287543.0" will return false for a long
long number1 = 0;
bool canConvert = long.TryParse(numString, out number1);
if (canConvert == true)
Console.WriteLine("number1 now = {0}", number1);
else
Console.WriteLine("numString is not a valid long");
byte number2 = 0;
numString = "255"; // A value of 256 will return false
canConvert = byte.TryParse(numString, out number2);
if (canConvert == true)
Console.WriteLine("number2 now = {0}", number2);
else
Console.WriteLine("numString is not a valid byte");
decimal number3 = 0;
numString = "27.3"; //"27" is also a valid decimal
canConvert = decimal.TryParse(numString, out number3);
if (canConvert == true)
Console.WriteLine("number3 now = {0}", number3);
else
Console.WriteLine("number3 is not a valid decimal");
StringBuilder
class TestStringBuilder
{
static void Main()
{
System.Text.StringBuilder sb = new System.Text.StringBuilder();
// Create a string composed of numbers 0 - 9
for (int i = 0; i < 10; i++)
{
sb.Append(i.ToString());
}
System.Console.WriteLine(sb); // displays 0123456789
// Copy one character of the string (not possible with a System.String)
sb[0] = sb[9];
System.Console.WriteLine(sb); // displays 9123456789
}
}