有一篇文章写了：iOS开发之NSString的几条实用技巧 ， 今天这篇，我们讲讲NSString的八条实用技巧。大家可以收藏起来，方便开发随时可以复制粘贴。
0.首字母大写
代码：
//首字母大写NSString *string = @"ligang";NSLog(@"string: %@",[string capitalizedString]);
打印：
2015-07-16 23:06:11.652 iOSStrongDemo[10279:3062010] string: Ligang1.分割字符串
代码：
//分割字符串NSString *string = @"This is a iOSDevTip";NSArray *array = [string componentsSeparatedByString:@"a"];NSString *string1 = [array objectAtIndex:0];NSString *string2 = [array objectAtIndex:1];NSLog(@"string1:%@ string2:%@",string1,string2);
打印：
2015-07-16 22:40:39.559 iOSStrongDemo[10165:3055448] string1:This is string2: iOSDevTip2.追加字符串
代码：
//追加字符串NSMutableString *string = [[NSMutableString alloc] initWithString:@"I Love "];[string appendString:@"China"];NSLog(@"string:%@",string);
打印：
2015-07-16 22:42:32.305 iOSStrongDemo[10189:3056410] string:I Love China3.插入字符串
代码：
//插入字符串NSMutableString *string = [[NSMutableString alloc] initWithString:@"I China"];[string insertString:@"Love " atIndex:2];NSLog(@"string: %@",string);
打印：
2015-07-16 22:44:10.706 iOSStrongDemo[10206:3057014] string: I Love China4.删除字符串
代码：
//删除字符串NSMutableString *string = [[NSMutableString alloc] initWithString:@"I love China"];[string deleteCharactersInRange:NSMakeRange(2, 4)];NSLog(@"String1: %@",string);
打印：
2015-07-16 22:46:58.437 iOSStrongDemo[10219:3057749] String1: I China5.判断是否包含前后缀
代码：
//判断是否包含前后缀NSString *string = @"I love China";BOOL isHasI = [string hasPrefix:@"I"];BOOL isHasChina = [string hasSuffix:@"China"];6.替换字符串
代码：
//替换字符串NSString *string = @"I love China";NSString *replaceString = [string stringByReplacingOccurrencesOfString:@"love" withString:@"like"];NSLog(@"replaceString: %@",replaceString);
打印：
2015-07-16 22:56:07.405 iOSStrongDemo[10236:3059503] replaceString: I like China7.去除字符串首尾的空格和换行符
代码：
//去除字符串首尾的空格和换行符NSString *string = @" I love China ";NSString *text = [string stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]];NSLog(@"text:%@",text);
打印：
2015-07-16 23:00:47.845 iOSStrongDemo[10265:3061013] text:I love China
代码已经更新，，demo下载地址：iOSStrongDemo
不能接受失败，也意味太想去成功了，从心理学上解释，
