The class of core processing strings in Bjective-c is NSString and nsmutablestring

objective-c The class in the core processing string is NSString with the nsmutablestring , the biggest difference between the two classes is NSString after the assignment is created, the content and length of the string cannot be changed dynamically unless the string is re-assigned. nsmutablestring creates an assignment to dynamically change the content and length on that string.

1. Create a classic nsstring string

NSString with the char* The big difference is NSString is a Objective Object , and char* is a byte array. The @+ " string " is the standard usage of objective-c nsstring string constants, char* No need to add @ when creating

2. -(void) viewdidload
4. {
6. [Super Viewdidload];
10. Classic string Assignment
12. NSString *STR0 = @ "I am the Rain pine Momo";
16. The string formatting merge includes each of the
18. nsstring* type int type char* type
20. NSString *str1 = [NSString stringwithformat:@ "My Name:%@ my age:%d my mailbox:%s", @ "Yu song Momo", "[email protected]"];
24. String assignment parameter can only write a string and the first kind of very similar
26. NSString *STR2 = [NSString stringwithstring:@ "I am the string"];
30. Convert string to utf-8 format parameter to char* type
32. NSString *STR3 = [NSString stringwithutf8string: "String conversion utf-8 format"];
38. String merge
40. int i = 100;
42. char*c = "Xuanyusong";
44. NSString *temp = @ "I am a temporary string";
48. The base of the string temp continues to add int i with char* c to form a new string
50. NSString *STR4 = [Temp stringbyappendingformat:@ "integer:%d character type:%s", I,c];
54. On the basis of the string temp continue to add temp and compose a new string
56. NSString *STR5 = [temp stringbyappendingstring:temp];
60. String output
62. NSLog (@ "STR0 =%@", STR0);
64. NSLog (@ "str1 =%@", str1);
66. NSLog (@ "str2 =%@", str2);
68. NSLog (@ "STR3 =%@", STR3);
70. NSLog (@ "STR4 =%@", STR4);
72. NSLog (@ "STR5 =%@", STR5);
76. }

2. traversal of strings

each string is actually made up of several Char character, the traversal of a string actually extracts every character in a string.

2. -(void) viewdidload
4. {
6. [Super Viewdidload];
10. Classic string Assignment
12. NSString *str = @ "Yusongmomo";
16. The length of the string
18. int count = [str length];
22. NSLog (@ "The length of the string is%d", count);
26. Iterate through every character in a string
28. for (int i =0; i < count; i++)
30. {
32. char c = [str characteratindex:i];
34. NSLog (@ "string%d bits is%c", i,c);
36. }
40. }

3. Comparison of strings

isequaltostring compares strings for exact equality, not identical in case, and does not match exactly.

Hasprefixe Match String Header

Hasuffix match the tail of a string

2. -(void) viewdidload
4. {
6. [Super Viewdidload];
12. NSString *str0 = @ "Rain pine Momo";
14. NSString *str1 = @ "Rain pine Momo";
20. String exact equality Comparison
22. if ([Str0 ISEQUALTOSTRING:STR1])
24. {
26. NSLog (@ "string is exactly equal");
28. }
32. Strings are compared at the beginning
34. if ([Str0 hasprefix:@ "Rain Pine"])
36. {
38. NSLog (@ "String str0 begins with a rain pine");
40. }
44. Strings are compared at the end
46. if ([str1 hassuffix:@ "MOMO"])
48. {
50. NSLog (@ "str1 string ends with Momo");
52. }
54. }

4. string interception and case change

2. -(void) viewdidload
4. {
6. [Super Viewdidload];
12. NSString *str0 = @ "Chinese name is Xuanyusong";
16. Intercepts the starting point of a string to the content between index 4
18. NSString * to = [STR0 substringtoindex:4];
22. NSLog (@ "to =%@", to);
26. Intercepts the contents of the character index from 2 to the end
28. NSString * from = [STR0 substringfromindex:2];
32. NSLog (@ "from =%@", from);
38. Set the range of intercept strings
40. From second place to tenth place
42. Nsrange rang = Nsmakerange (2, 10);
44. NSString * Strrang = [Str0 Substringwithrange:rang];
46. NSLog (@ "rang =%@", Strrang);
50. Set the string to capitalize the first letter
52. NSLog (@ "STR0 First Capital:%@", [Str0 capitalizedstring]);
54. Sets the entire contents of the string to uppercase
56. NSLog (@ "STR0 Capital:%@", [Str0 uppercasestring]);
58. Set the character to all lowercase
60. NSLog (@ "Str0 lowercase:%@", [Str0 lowercasestring]);
64. }

5. searching strings and replacing strings

2. -(void) viewdidload
4. {
6. [Super Viewdidload];
12. NSString *str0 = @ "Chinese name is Xuanyusong";
14. NSString *temp = @ "is";
16. Nsrange rang = [Str0 rangeofstring:temp];
20. NSLog (@ "The string searched at the starting point in Str0 of index%d", rang.location);
22. NSLog (@ "The string searched at the end of the STR0 in the index is%d", rang.location + rang.length);
26. Replace a string in a search with a new string
28. NSString *str = [str0 stringbyreplacingcharactersinrange:rang withstring:@ "wow ka ka Kaka"];
30. NSLog (@ "replacement string is%@", str);
36. Replace All "" in the string with *
38. str = [STR0 stringbyreplacingoccurrencesofstring: @ "" withstring:@ "@"];
40. NSLog (@ "replacement string is%@", str);
46. }

Expand: Use the following method to replace the whole string and set the replacement area. ons:<# (nsstringcompareoptions) #> range:<# (nsrange) #>

Stringbyreplacingoccurrencesofstring: (NSString *) withstring: (NSString *) options: (nsstringcompareoptions) Range: ( Nsrange)

The class of core processing strings in Bjective-c is NSString and nsmutablestring