Common uses of IOS NSString

Restudying, often new//1, creating constant strings.

NSString *astring = @ "This is a string!";

2, create an empty string, give the assignment.

NSString *astring = [[NSString alloc] init];

Astring = @ "This is a string!";

[Astring release];

NSLog (@ "astring:%@", astring);

//

NSString *astring = [[NSString alloc] init];

NSLog (@ "0x%.8x", astring);

[Email protected] "This is a string!";

NSLog (@ "0x%.8x", astring);

[Astring release];

NSLog (@ "astring:%@", astring);

3, in the above method, lifting speed: Initwithstring method

NSString *astring = [[NSString alloc] initwithstring:@ "This is a string!"];

NSLog (@ "astring:%@", astring);

[Astring release];

4. Create a string with standard C: Initwithcstring method

Char *cstring = "This is a string!";

NSString *astring = [[NSString alloc] initwithcstring:cstring];

NSLog (@ "astring:%@", astring);

[Astring release];

5. Create a formatted string: placeholder (composed of one% plus one character)

int i = 1;

int j = 2;

NSString *astring = [[NSString alloc] initwithstring:[nsstring stringwithformat:@ "%d.this is%i string!", I,j]];

NSLog (@ "astring:%@", astring);

[Astring release];

6. Create a temporary string

NSString *astring;

astring = [NSString stringwithcstring: "This is a temporary string"];

NSLog (@ "astring:%@", astring);

7. Create a string from a file

NSString *path = [[Nsbundlemainbundle] pathforresource:@ "Astring.text" oftype:nil];

NSString *astring = [[NSString alloc] initwithcontentsoffile:path];

NSLog (@ "astring:%@", astring);

[Astring release];

8. Create a string with a string and write to the file

NSString *astring = [[NSString alloc] initwithstring:@ "This is a string!"];

NSLog (@ "astring:%@", astring);

NSString *path = @ "Astring.text";    

[astring Writetofile:path Atomically:yes];

[Astring release];  

Note: This path is only indicative, the true path is not so//9, c comparison: strcmp function

Char string1[] = "string!";

Char string2[] = "string!";

if (strcmp (string1, string2) = = 0)
{

    NSLog (@ "1");

}

10. Isequaltostring method

NSString *ASTRING01 = @ "This is a string!";

NSString *astring02 = @ "This is a string!";

BOOL result = [Astring01 isequaltostring:astring02];

NSLog (@ "result:%d", result);

11. Compare method (three values returned by comparer)

//
NSString *ASTRING01 = @ "This is a string!";

NSString *astring02 = @ "This is a string!";    

BOOL result = [Astring01 compare:astring02] = = Nsorderedsame;    Nsorderedsame judge whether the content is the same

NSLog (@ "result:%d", result);    

//
NSString *ASTRING01 = @ "This is a string!";

NSString *astring02 = @ "This is a string!";

BOOL result = [Astring01 compare:astring02] = = nsorderedascending;    Nsorderedascending determines the size of two object values (in alphabetical order, astring02 greater than ASTRING01 is true)

NSLog (@ "result:%d", result);

//
NSString *ASTRING01 = @ "This is a string!";

NSString *astring02 = @ "This is a string!";

BOOL result = [Astring01 compare:astring02] = = nsordereddescending;    Nsordereddescending determines the size of two object values (in alphabetical order, ASTRING02 is less than astring01 true)

NSLog (@ "result:%d", result);     

12, do not consider case comparison string

1.
NSString *ASTRING01 = @ "This is a string!";

NSString *astring02 = @ "This is a string!";

BOOL result = [Astring01 caseinsensitivecompare:astring02] = = Nsorderedsame;    Nsordereddescending determines the size of two object values (in alphabetical order, ASTRING02 is less than astring01 true)



2.
NSString *ASTRING01 = @ "This is a string!";

NSString *astring02 = @ "This is a string!";

BOOL result = [Astring01 compare:astring02

Options:nscaseinsensitivesearch | Nsnumericsearch] = = Nsorderedsame;    Nscaseinsensitivesearch: Case-insensitive comparison nsliteralsearch: Make a full comparison, case-sensitive nsnumericsearch: Compares the number of characters in a string, not the character value.

13. Output uppercase or lowercase strings

NSLog (@ "string1:%@", [string1 uppercasestring]);//Uppercase

NSLog (@ "string2:%@", [string2 lowercasestring]);//lowercase

NSLog (@ "string2:%@", [string2 capitalizedstring]);//initial Letter size

14,-rangeofstring://Find if string somewhere contains other strings

NSString *string1 = @ "This is a string";

NSString *string2 = @ "string";

Nsrange range = [string1 rangeofstring:string2];

int location = Range.location;

int leight = Range.length;

NSString *astring = [[NSString alloc] initwithstring:[nsstring stringwithformat:@ "location:%i,leight:%i", location, Leight]];

NSLog (@ "astring:%@", astring);

[Astring release];

15.-substringtoindex: Truncate from the beginning of the string to the specified position, but not the character of the position

NSString *string1 = @ "This is a string";

NSString *string2 = [string1 substringtoindex:3];

NSLog (@ "string2:%@", string2);

16.-substringfromindex: Start at the specified position (including the character at the specified position) and include all subsequent characters

NSString *string1 = @ "This is a string";

NSString *string2 = [string1 substringfromindex:3];

NSLog (@ "string2:%@", string2);

17,-substringwithrange://In accordance with the given position, length, arbitrarily intercept the substring from the string

NSString *string1 = @ "This is a string";

NSString *string2 = [string1 substringwithrange:nsmakerange (0, 4)];

NSLog (@ "string2:%@", string2);

18,-stringwithcapacity://Generate empty string according to fixed length

Nsmutablestring *string;

String = [nsmutablestring stringwithcapacity:40];

19,-appendstring:and-appendformat://Put one string at the end of another string

nsmutablestring *string1 = [[Nsmutablestring alloc] initwithstring:@ "This is a nsmutablestring"];

[String1 appendstring:@], I'll be adding some character "];

[String1 appendformat:[nsstring stringwithformat:@ ", I'll be adding some character"]];

NSLog (@ "string1:%@", String1);

20,-insertstring:atindex://Insert string at specified position

nsmutablestring *string1 = [[Nsmutablestring alloc] initwithstring:@ "This is a nsmutablestring"];

[String1 insertstring:@] hi! [atindex:0];

NSLog (@ "string1:%@", String1);

21,-setstring:

nsmutablestring *string1 = [[Nsmutablestring alloc] initwithstring:@ "This is a nsmutablestring"];

[String1 setstring:@ "Hello word!"];

NSLog (@ "string1:%@", String1);

22,-replacecharactersinrange:withstring://Replace a string in a specified position and length with a specified string

nsmutablestring *string1 = [[Nsmutablestring alloc] initwithstring:@ "This is a nsmutablestring"];

[String1 replacecharactersinrange:nsmakerange (0, 4) withstring:@ "that"];

NSLog (@ "string1:%@", String1);

23,-hasprefix://Check whether the string starts with another string

@ "NSStringInformation.txt";

[String1 Hasprefix:@ "nsstring1? NSLog (@ "YES"): NSLog (@ "NO");

[String1 Hassuffix:@ ". txt 1? NSLog (@ "YES"): NSLog (@ "NO");        

24. Extension path

NSString *path = @ "~/nsdata.txt";

NSString *absolutepath = [Path Stringbyexpandingtildeinpath];

NSLog (@ "absolutepath:%@", Absolutepath);

NSLog (@ "path:%@", [Absolutepath Stringbyabbreviatingwithtildeinpath]);

25. File name extension

NSString *path = @ "~/nsdata.txt";

NSLog (@ "extension:%@", [Path pathextension]);

Common uses of IOS NSString