ios 字符串的比较

 

 

 

  // 声明一个NSString 

NSString *str; 
// 使用stringWithFormat生成一格式化字符串 
str = [NSString stringWithFormat:@"This is %@","John"]; 
NSLog(@"str--->%@",str); 
// 字符串长度length; 
NSLog(@"The length of this string is %@",[str length]); 
// 字符串比较 isEqualToString, 返回NO(false)，isEqualToString区分大小写 
BOOL isequal = [str isEqualToString:@"this is John"]; 
 
// 字符串序列比列 compare,返回结果NSComparisonResult 
// type enum _NSComparisonResult{ 
//     NSOrderedAscending = -1, 
//     NSOrderedSame, 
//     NSOrderedDescending 
        // } 
int result = [@"bool" compare:@"cool"]; 
NSLog(@"The result is %d",result); 
 
// compare 比较规则options 
// NSLiteralSearch 区分大小写(完全比较) 
// NSCaseInsensitiveSearch 不区分大小写 
// NSNumericSearch 只比较字符串的个数，而不比较字符串的字面值 
int result1 = [@"This is John" compare:@"this is John" options:NSCaseInsensitiveSearch | NSNumericSearch]; 
NSLog(@"The result is %d",result1); 
 
// 字符串开头是否包括另一字符串 hasPrefix,返回结果YES(true) 
BOOL isHas = [str hasPrefix:@"This"]; 
// 字符串结尾是否包括另一字符串 hasSuffix,返回结果YES(true) 
BOOL isHas = [str hasSuffix:@"John"]; 
 
// 查找字符串在另一字符串中的位置 
NSRange range = [str rangeOfString:@"is" options:NSCaseInsensitiveSearch]; 
NSLog(@"The location in the string named 'str' of 'is' is @d",range.location);