OPI_LR2011_ch2m1
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string stringOne = "Line one\nline Two"; string stringTwo = @"Line One
line Two";
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3.2.3 System.Object.ToString()
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int myint = 10;
string intstring = myint.ToString() ;
@ ToString() '] myint
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Concat() – ^] Y ; Copy() – ^] ;
Equals() – ], ;
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Format() – + ] , ^ +-
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Intern() – ] ^ ; Join() – ] - ( ^ -
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2h rs – ; Length – ;
2l n () – ] ^ ; CompareTo() –^] Y;
CopyTo() – ^] Unicode
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EndsWith() – ], ] ^ -
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Insert() – ] ( ^;
LastIndexOf() – ] (
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PadLeft() – ^] ^, ^
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PadRight() – ^] ^, ^
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Remove() – ] ;
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StartsWith() – ], ] -
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Substring() – ] ; ToCharArray() – ^] ; ToLower() – ( ; ToUpper() – ;
Trim() – ] (
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TrimStart() – ] (
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, \ ] Compare(), Concat(), Copy(),
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Insert() Y. @ ] - ^ textBox1.
private void button1_Click(object sender, EventArgs e)
{
string str1 = "PYS_"; string str2 = "|}X~";
string str3 = @"C# S \ Y k T Z^< "+
"`SR_ S Z P TS .NET P q Z<R"; int result;
//< R ZTS Z TS
//SR ZR S^\< P Rh ^ q^ iTk Compare ZTS result = string.Compare (str1, str2);
textBox1.Text = "ZTS k\< str1: " + str1 + " T str2: " + str2 + ", Z Q^ [ P: " + result + "\r\n";
//SR ZR S^\< q^ iTk Compare Q P SR< PZP< Z < // T_Z^SP Z_T Z^ Z P
result = string.Compare(str1, str2, true);
textBox1.Text = textBox1.Text + "O ZTS k\< Y Q SZPs S^SP Z_T Z^";
textBox1.Text = textBox1.Text + "str1: " + str1 + " T str2: " + str2 + ", Z Q^ [ P: " + result + "\r\n";
// < R Y'\ P Z TS
//SR ZR S^\< q^ iTk Z TS string str4 = string.Concat(str1, str2);
textBox1.Text = textBox1.Text + "m S Zk\< str4 ` s < " + "Y'\ P str1 T str2: " + str4 + "\r\n";
//SR ZR S^\< Z SP Pt Rl ZP Z
//Y'\ P Z TS
string str5 = str1 + str2;
textBox1.Text = textBox1.Text + "str5 = str1 + str2: " + str5 + "\r\n";
// SR ZR S^\< < Copy TkSP Z ^ string str6 = string.Copy(str5) ;
textBox1.Text = textBox1.Text + "str6 Tl SP P Q str5: " + str6 + "\r\n";
//SR ZR S^\< Z SP Pt Rl ZP Z TkSP
string str7 = str6;
textBox1.Text = textBox1.Text + "str7 = str6: " + str7 + "\r\n";
//T [ P YTS ZTS
//SR ZR S^khR < Equals P<_ Y'\ P
textBox1.Text = textBox1.Text + "str7.Equals(str6): " + str7.Equals(str6) + "\r\n";
//SR ZR S^khR P Rh Rl < Equals
44
textBox1.Text = textBox1.Text + "str7 T str6 ZTS T?: " + string.Equals(str7, str6) + "\r\n";
//SR ZR S^khR ZP Z ==
textBox1.Text = textBox1.Text + "str7==str6? " + (str7 == str6) + "\r\n";
//SRQ Ph StR R Z P
textBox1.Text = textBox1.Text + "p str7 <P\ StR ^ " + str7.Length + "R<S TS" + "\r\n";
//SRQ Ph R<S ^ Z P l_ T ^
textBox1.Text = textBox1.Text + "O'R< < < ^ Z ^ str7 \ R<S " + str7[4] + "\r\n";
//ZTS T i Z P TQ SsT R< Q < Z < textBox1.Text = textBox1.Text + "str3: " + str3 + "hR
€P T h^\ [ i l Z S < \"T Z^<\"? " + str3.EndsWith("T Z^<") + "\r\n";
//ZTS T i Z P TQ SsT R< Q < Z < textBox1.Text = textBox1.Text + "str3: " + str3 + "hR
€P T h^\ [ i l Z S < \"P q Z<P\"? " + str3.EndsWith("P q Z<P") + "\r\n";
//`^ Z`_ Ss t T Z R S Z
textBox1.Text = textBox1.Text + "O Z` Ss t SP T Z^<
^Z str3 <P\ T " + str3.IndexOf("T Z^<")+ "\r\n";
//S PS \< S S S Z
string str8 = str3.Insert(str3.IndexOf("P TS"), "^t Rs"); textBox1.Text = textBox1.Text + "str8: " + str8;
}
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ZTS k\< str1: PYS_ T str2: |}X~, Z Q^ [ P: -1
O ZTS k\< Y Q SZPs S^SP Z_T Z^str1: PYS_ T str2: |}X~, Z Q^ [ P: 0
m S Zk\< str4 ` s < Y'\ P str1 T str2: PYS_|}X~ str5 = str1 + str2: PYS_|}X~
str6 Tl SP P Q str5: PYS_|}X~ str7 = str6: PYS_|}X~ str7.Equals(str6): True
str7 T str6 ZTS T?: True str7==str6? True
p str7 <P\ StR ^ 8R<S TS
O'R< < < ^ Z ^ str7 \ R<S |
str3: C# S \ Y k T Z^< `SR_ S Z P TS
.NET P q Z<R •R QP T h^\ [ i l Z S < "T Z^<"? False str3: C# S \ Y k T Z^< `SR_ S Z P TS
.NET P q Z<R •R pP T h^\ [ i l Z S < "P q Z<P"? False O Z` Ss t SP T Z^< ^ Z str3 <P\ T 15 str8: C# S \ Y k T Z^< `SR_ S Z ^t Rs-
P TS .NET P q Z<R
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string str3 = @"m# Z PS \ Y k T Z^< " + "`SR _ S Z P TS .NET P q Z<R"; result = string.Compare(str1, str2);
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ZTS k\< strl: PYS_ T str2: |}X~, Z Q^ [ P : -1
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result = string.Compare(str1, str2, true);
textBox1.Text = textBox1.Text + "O ZTS k\< Y Q SZPs S^SP
Z _T Z^";
textBox1.Text = textBox1.Text + "str1: " + str1 + " T str2: " + str2 + ", Z Q^ [ P : " + result + "\r\n";
@ :
O ZTS k\< Y Q SZPs S^SP Z _T Z^ str1: PYS_, str2:|}X~, Z - Q^ [ P : 0
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String Str4 = string.Concat (str1, str2);
h – (+). string str5 = str1 +
str2;
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strl+str2, \ ], ^ -
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string str6 = string.Copy (str5); string Str7 = Str6;
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str5.
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str7.Equals(str6)
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string.Equals (str7, str6)
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textBox1.Text = "O'R< < < ^ Z ^ str7 \ R<S + str7[4];
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3.2.5 A Y 8 43 87
= string ] ( Substring()
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//_`^\< Z YZ Y R string s1 = "r R oSP ZR • RZR";
//Zt^\< T P [_ Z YT ^ int ix = s1.LastIndexOf(" ");
//Zt^\< P \ S S Z ^ string s2 = s1.Substring (ix+1);
//S P S k\< s1 P T Z ^, j hR P\ [
// 0- _ T ^, j l QP T h^\ [ P T< Z YT < s1 = s1.Substring(0, ix) ;
//Q S^ `^ P\< T P [_ Z YT ^ ix = s1.LastIndexOf(" ");
//S P S k\< s3 P P \ S Z ^ string s3 =s1.Substring(ix+1);
//R P\< si P T Z ^
//ST ^ [ S_ R<S ^ ix
s1 = s1.Substring(0,ix);
//R P\< ix P Z YT
//<Tt "R" T "SP"
ix = s1.LastIndexOf(" ");
//S P S k\< s4 P T Z ^ T string s4 = s1.Substring (ix+1) ; //S P S k\< s1 P T Z ^ ST 0 ix //Zt^\< T [ R S "R"
s1 = s1.Substring(0,ix);
//P<P_P\< ZtP R T P [_ Z YT ^
//P i[_ ZPQ^ q^ iT LastIndexof S Z -1 ix = s1.LastIndexOf(" ");
//S P S k\< s5 P T Z ^ hR PkhR Q
//T [ R ix = 1, s5 S P S k\ [ P hP s1 string s5 =s1.Substring(ix+1);
//XRS R< Z Q^ [ P
textBox3.Text = "s2: " + s2 + "\r\n" + "s3: " + s3 + "\r\n";
48
textBox3.Text = textBox3.Text + "s4: " + s4 + "\r\n" + "s5: " + s5 + "\r\n";
textBox3.Text = textBox3.Text + "s1: " + s1 + "\r\n";
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string s1 = "r R oSP ZR • RZR";
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int ix = s1.LastIndexOf(" ") ;
ix ^ 12. 2 «0-
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string s2 = s1.Substring(ix+1);
s2 «0». h ]
s1 «0». h + ^ Substring – . '
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s1 = s1.Substring(0, ix);
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ix = s1.LastIndexOf(" ");
=, + (-1 + 1 = 0),
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string s5 = s1.Substring(ix+1) ;
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s2: • RZR s3: ZR s4: oSP s5: r R s1: r R
3.2.6 9 # 7 2 2384"
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, ] , \ Split()
string. Split() ] . h -
Split()
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// Z P P TQ^
string s1 = "r R ,oSP, ZR, p Z QY Z^";
//QP P\< Z Q T ST R<S R P P TQ^ const char cspace = ' ';
const char ccomma = ',';
//S Zk\< <P RS Z Q T SRs R<S TS
//T T TiTP TQ^\< l _ S <P < P<R char[] delimiters = {cspace, ccomma};
string output = ""; int ctr = 1;
//SR T \< T Z R P ST Z Q T [ R TS
//T QY ZT_P\< Z Q^ [ P
foreach (string substring in s1.Split(delimiters))
{
output += ctr++; // < Z T Z R output += ": ";
output += substring; // T Z P
output += "\r\n"; // Z sT P S^ T Tk
}
// SRST Z Q^ [ P ^ textBox4.Text = output;
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1:r R
2:oSP
3:ZR
5:p
7:Z QY Z^
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string s1 = "r R ,oSP, ZR, p Z QY Z^";
s1, \ Y . -
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const char cspace = ' '; const char ccomma = ',';
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{ ] ^ .
char[] delimiters = {cspace, ccomma};
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foreach (string substring in s1.Split(delimiters))
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3.2.7 6 StringBuilder
9 StringBuilder ] -
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StringBuilder ]:
Capacity – ] , -
StringBuilder;
Chars – 1 ;
Length – ] ( '] StringBuilder;
t – ] , -
StringBuilder;
Append() – ] '] StringBuilder; AppendFormat() – \ ] ^] +
StringBuilder;
Ensurecapacity() – ], \ StringBuilder ] ]
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