NSString 兩個(gè)字符串的比較，用 a compare:b 來比富腊，得出的結(jié)果分3種
-
26個(gè)字母比較 越靠后面 越大
NSString *a = @"qweqwe";
NSString *b = @"qweasd";
BOOL result = [a compare:b];
if (result == NSOrderedSame) { // NSOrderedSame = 0 完全一樣
NSLog(@"a = b");
}else if(result == NSOrderedAscending) // NSOrderedAscending = -1
NSLog(@"a < b");
else{ //NSOrderedDescending = +1
NSLog(@"a > b");
}2011-07-05 15:04:33.951 Q[5180:207] a > b
2.比較數(shù)字或者符號(hào)蛆挫，或者字母 什么都行
NSString *a = @"1.0.30qweqwe";
NSString *b = @"1.0.45qweasd";
BOOL result = [a compare:b];
if (result == NSOrderedSame) { // NSOrderedSame = 0 完全一樣
NSLog(@"a = b");
}else if(result == NSOrderedAscending) // NSOrderedAscending = -1
NSLog(@"a < b");
else{ //NSOrderedDescending = +1
NSLog(@"a > b");
}
2011-07-05 15:05:13.175 Q[5209:207] a < b
3.不考慮大小寫比較字符串
[a caseInsensitiveCompare:b]
- (void)viewDidLoad
{
NSString *a = @"i love my boyfriend.";
NSString *b = @"I Love My Boyfriend.";
NSLog(@" \n a: %@ \n",a);
NSLog(@" \n b: %@ \n",a);
BOOL result = [a caseInsensitiveCompare:b] == NSOrderedSame;
｝
// result = (BOOL) YES;
4.不考慮大小寫比較字符串
[a caseInsensitiveCompare:b]
- (void)viewDidLoad
{
NSString *a = @"i love my boyfriend.";
NSString *b = @"Little baby.";
NSLog(@" \n a: %@ \n",a);
NSLog(@" \n b: %@ \n",a);
BOOL result = [a caseInsensitiveCompare:b] == NSOrderedAscending;
}
//result = (BOOL) YES;
- 有選擇的比較大小 [a compare:b options:NSCaseInsensitiveSearch|NSNumericSearch]
- (void)viewDidLoad
{
NSString *a = @"i love my boyfriend.";
NSString *b = @"I Love My Boyfriend.";
NSLog(@" \n a: %@ \n",a);
NSLog(@" \n b: %@ \n",b);
BOOL result = [a compare:b options:NSCaseInsensitiveSearch|NSNumericSearch] == NSOrderedSame;
}
//result = (BOOL)YES;
NSCaseInsensitiveSearch 忽略大小寫的比較字符串
NSNumericSearch 比較字符串的個(gè)數(shù)
NSLiteralSearch 區(qū)分大小寫赃承，進(jìn)行完全比較
