iOS Learning Note (33) basic use of--nsstring

A string is cut into an array componentsseparatedbystring

Two iOS string removal of special symbols stringbytrimmingcharactersinset should be used for account login etc.

First, the previous example:

NSString * str1 =[nameinput.text Stringbytrimmingcharactersinset:[nscharactersetwhitespaceandnewlinecharacterset]] ;

NSString * str2 =[passwdinput.text Stringbytrimmingcharactersinset:[nscharactersetwhitespaceandnewlinecharacterset ]];

[Self.delegate loginactioninview:self name:str1 PASSWD:STR2];

Reprinted from: http://blog.csdn.net/aiyongyyy/article/details/8269546

You can use the Stringbytrimmingcharactersinset function in iOS to filter special symbols in a string

First define a nscharacterset, including special symbols that need to be removed.

Nscharacterset *set = [nscharacterset charactersetwithcharactersinstring: @ "@/:; () ¥" ", []{}#%-*+=_\\|~<> $€^ ' @#$%^&* () _+ ' \ ""];

Because there are full-width and half-width symbols in the nsstring, some symbols include full-width and half-width

Then call Stringbytrimmingcharactersinset

NSString *trimmedstring = [string stringbytrimmingcharactersinset:set];

Trimmedstring is the filtered string.

----------------------------------------------------------

Http://blog.sina.com.cn/s/blog_5421851501014xif.html

RemoveusernameThe space in the table Newline,nextline
The code is as follows: (three lines of code)

Nscharacterset *whitespace = [NscharactersetWhitespaceandnewlinecharacterset];

NSString *username= [Musernamefield stringvalue];

Username = [usernameStringbytrimmingcharactersinset: whitespace];



Notes：

Stringbytrimmingcharactersinset:
Returns a new string made by removing from both ends of the receiver characters contained in a given character set.

Whitespaceandnewlinecharacterset
Returns a character set containing only the whitespace characters space (u+0020) and tab (u+0009) and the newline and next Line characters (u+000a–u+000d, u+0085).

Alternatively, you can useWhitespacecharactersetReplaceWhitespaceandnewlinecharactersetDifference newline nextline
Whitespacecharacterset
Returns a character set containing only the in-line whitespace characters space (u+0020) and tab (U+0009).

NSString *temptext = [messageTextField.text stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceCharacterSet]];
NSString *text = [temptext stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet ]];

Line 1th is to remove the 2-terminal space

Line 2nd is to remove the carriage return

Search method in three NSString rangofstring

2. NSString *str1 = @"Can you \ \ Speak 中文版";
4. NSString *str = @"\ n";
6. //Search in str1 this string \ n to determine if there is
8. if ([str1 rangeofstring:str].location! = nsnotfound) {
10. NSLog (@"This string has \ n");
12. }
14. //rangeofstring The preceding argument is the string to be searched, followed by the character to be searched
16. //nsnotfound indicates that a request operation is something or item is not found, or does not exist

iOS Learning Note (33) basic use of--nsstring