来自http://devtang.com/blog/2012/02/14/nsstring-java-like-wrapper/
NSStringWrapper.h
#import <Foundation/Foundation.h>
@interface NSString(Wrapper)
/** Return the char value at the specified index. */
- (unichar) charAt:(int)index;
/**
* Compares two strings lexicographically.
* the value 0 if the argument string is equal to this string;
* a value less than 0 if this string is lexicographically less than the string argument;
* and a value greater than 0 if this string is lexicographically greater than the string argument.
*/
- (int) compareTo:(NSString*) anotherString;
- (int) compareToIgnoreCase:(NSString*) str;
- (BOOL) contains:(NSString*) str;
- (BOOL) startsWith:(NSString*)prefix;
- (BOOL) endsWith:(NSString*)suffix;
- (BOOL) equals:(NSString*) anotherString;
- (BOOL) equalsIgnoreCase:(NSString*) anotherString;
- (int) indexOfChar:(unichar)ch;
- (int) indexOfChar:(unichar)ch fromIndex:(int)index;
- (int) indexOfString:(NSString*)str;
- (int) indexOfString:(NSString*)str fromIndex:(int)index;
- (int) lastIndexOfChar:(unichar)ch;
- (int) lastIndexOfChar:(unichar)ch fromIndex:(int)index;
- (int) lastIndexOfString:(NSString*)str;
- (int) lastIndexOfString:(NSString*)str fromIndex:(int)index;
- (NSString *) substringFromIndex:(int)beginIndex toIndex:(int)endIndex;
- (NSString *) toLowerCase;
- (NSString *) toUpperCase;
- (NSString *) trim;
- (NSString *) replaceAll:(NSString*)origin with:(NSString*)replacement;
- (NSArray *) split:(NSString*) separator;
@end
==============================================
NSStringWrapper.m
#import "NSStringWrapper.h"
@implementation NSString(Wrapper)
#define JavaNotFound -1
/** Java-like method. Returns the char value at the specified index. */
- (unichar) charAt:(int)index {
return [self characterAtIndex:index];
}
/**
* Java-like method. Compares two strings lexicographically.
* the value 0 if the argument string is equal to this string;
* a value less than 0 if this string is lexicographically less than the string argument;
* and a value greater than 0 if this string is lexicographically greater than the string argument.
*/
- (int) compareTo:(NSString*) anotherString {
return [self compare:anotherString];
}
/** Java-like method. Compares two strings lexicographically, ignoring case differences. */
- (int) compareToIgnoreCase:(NSString*) str {
return [self compare:str options:NSCaseInsensitiveSearch];
}
/** Java-like method. Returns true if and only if this string contains the specified sequence of char values. */
- (BOOL) contains:(NSString*) str {
NSRange range = [self rangeOfString:str];
return (range.location != NSNotFound);
}
- (BOOL) startsWith:(NSString*)prefix {
return [self hasPrefix:prefix];
}
- (BOOL) endsWith:(NSString*)suffix {
return [self hasSuffix:suffix];
}
- (BOOL) equals:(NSString*) anotherString {
return [self isEqualToString:anotherString];
}
- (BOOL) equalsIgnoreCase:(NSString*) anotherString {
return [[self toLowerCase] equals:[anotherString toLowerCase]];
}
- (int) indexOfChar:(unichar)ch{
return [self indexOfChar:ch fromIndex:0];
}
- (int) indexOfChar:(unichar)ch fromIndex:(int)index{
int len = self.length;
for (int i = index; i < len; ++i) {
if (ch == [self charAt:i]) {
return i;
}
}
return JavaNotFound;
}
- (int) indexOfString:(NSString*)str {
NSRange range = [self rangeOfString:str];
if (range.location == NSNotFound) {
return JavaNotFound;
}
return range.location;
}
- (int) indexOfString:(NSString*)str fromIndex:(int)index {
NSRange fromRange = NSMakeRange(index, self.length - index);
NSRange range = [self rangeOfString:str options:NSLiteralSearch range:fromRange];
if (range.location == NSNotFound) {
return JavaNotFound;
}
return range.location;
}
- (int) lastIndexOfChar:(unichar)ch {
int len = self.length;
for (int i = len-1; i >=0; --i) {
if ([self charAt:i] == ch) {
return i;
}
}
return JavaNotFound;
}
- (int) lastIndexOfChar:(unichar)ch fromIndex:(int)index {
int len = self.length;
if (index >= len) {
index = len - 1;
}
for (int i = index; i >= 0; --i) {
if ([self charAt:i] == ch) {
return index;
}
}
return JavaNotFound;
}
- (int) lastIndexOfString:(NSString*)str {
NSRange range = [self rangeOfString:str options:NSBackwardsSearch];
if (range.location == NSNotFound) {
return JavaNotFound;
}
return range.location;
}
- (int) lastIndexOfString:(NSString*)str fromIndex:(int)index {
NSRange fromRange = NSMakeRange(0, index);
NSRange range = [self rangeOfString:str options:NSBackwardsSearch range:fromRange];
if (range.location == NSNotFound) {
return JavaNotFound;
}
return range.location;
}
- (NSString *) substringFromIndex:(int)beginIndex toIndex:(int)endIndex {
if (endIndex <= beginIndex) {
return @"";
}
NSRange range = NSMakeRange(beginIndex, endIndex - beginIndex);
return [self substringWithRange:range];
}
- (NSString *) toLowerCase {
return [self lowercaseString];
}
- (NSString *) toUpperCase {
return [self uppercaseString];
}
- (NSString *) trim {
return [self stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]];
}
- (NSString *) replaceAll:(NSString*)origin with:(NSString*)replacement {
return [self stringByReplacingOccurrencesOfString:origin withString:replacement];
}
- (NSArray *) split:(NSString*) separator {
return [self componentsSeparatedByString:separator];
}
@end