ios 不区分字符串大小写的比较

 1         NSString *str;
 2         // 使用stringWithFormat生成一格式化字符串
 3         str = [NSString stringWithFormat:@"This is %@","John"];
 4         NSLog(@"str--->%@",str);
 5         // 字符串长度length;
 6         NSLog(@"The length of this string is %@",[str length]);
 7         // 字符串比较 isEqualToString, 返回NO(false)，isEqualToString区分大小写
 8         BOOL isequal = [str isEqualToString:@"this is John"];
 9
10         // 字符串序列比列 compare,返回结果NSComparisonResult
11         // type enum _NSComparisonResult{
12         // NSOrderedAscending = -1,
13         // NSOrderedSame,
14         // NSOrderedDescending
15         // }
16         int result = [@"bool" compare:@"cool"];
17         NSLog(@"The result is %d",result);
18
19         // compare 比较规则options
20         // NSLiteralSearch 区分大小写(完全比较)
21         // NSCaseInsensitiveSearch 不区分大小写
22         // NSNumericSearch 只比较字符串的个数，而不比较字符串的字面值
23         int result1 = [@"This is John" compare:@"this is John" options:NSCaseInsensitiveSearch | NSNumericSearch];
24         NSLog(@"The result is %d",result1);
25
26         // 字符串开头是否包括另一字符串 hasPrefix,返回结果YES(true)
27         BOOL isHas = [str hasPrefix:@"This"];
28         // 字符串结尾是否包括另一字符串 hasSuffix,返回结果YES(true)
29         BOOL isHas = [str hasSuffix:@"John"];
30
31         // 查找字符串在另一字符串中的位置
32         NSRange range = [str rangeOfString:@"is" options:NSCaseInsensitiveSearch];
33         NSLog(@"The location in the string named ‘str‘ of ‘is‘ is @d",range.location);