-------------------------------------------------------------------------NSString-------------------------------------------------------------------------------
1:NSData 转换成 NSString
NSString *aString = [[NSString alloc] initWithData:adataencoding:NSUTF8StringEncoding];
2:获取NSString 扩展后缀 (abc.txt) 如果没有后缀,返回的字符串长度为0
NSString *strFileExtension = [strFilePath pathExtension];
3:利用NSRange 进行字符串截取
NSRange range = NSMakeRange(1, 2); NSLog(@"%@",[@"余书懿" substringWithRange:range]);
输出:书懿
还可以从头开发截取,或者从末尾开始截取
NSLog(@"%@",NSTemporaryDirectory()); NSLog(@"%@",[NSTemporaryDirectory() substringFromIndex:2]); // NSLog(@"%@",[NSTemporaryDirectory() substringToIndex:2]);
输出:
2012-11-07 09:51:58.020 FEMicroCoop[1558:c07] /Users/amarishuyi/Library/Application Support/iPhone Simulator/6.0/Applications/1795A32F-605D-4C10-8903-A70668048C76/tmp/
2012-11-07 09:51:59.257 FEMicroCoop[1558:c07]/Users/amarishuyi/Library/Application Support/iPhone Simulator/6.0/Applications/1795A32F-605D-4C10-8903-A70668048C76/tmp/
2012-11-07 09:52:13.126 FEMicroCoop[1558:c07] /Users/amarishuyi/Library/Application Support/iPhone Simulator/6.0/Applications/1795A32F-605D-4C10-8903-A70668048C76/tmp/
注:红色表示被截取掉的.
4:大小写转换
[@"abc" uppercaseString]; //大写 [@"ABC" lowercaseString]; //小写
5:字符串编码格式转换:
转换成Url 可以接受的格式
self.attachmentUrlString = [self.attachmentUrlString stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
转换回来
NSString *encodeFilePathString = [self.filePathString stringByReplacingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
6:判断NSString 是否包含中文
NSString *str = @"i'm a 苹果。...";
for(int i=0; i< [str length];i++){
int a = [str characterAtIndex:i];
if( a > 0x4e00 && a < 0x9fff)
NSLog(@"汉字");
}
7:根据字符串长度计算所占用的实际空间
NSLog(@"%@",NSStringFromCGSize([testString sizeWithFont:[UIFont systemFontOfSize:10]]));这里根据字体设定的大小来确定CGSize
subtitleSize = [subtitleText sizeWithFont:[UIFont systemFontOfSize:12]
constrainedToSize:CGSizeMake(180.0, 4000)
lineBreakMode:UILineBreakModeWordWrap];这个用来确认每一行以
180像素的宽度,然后自动换行
UILineBreakModeWordWrap需要用多少占用面积.多用在计算每一列UITableViewCell的高度
8:去掉字符串两段空格和回车
searchResult = [searchResult stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet ]];
9:将字符串分割为数组
NSArray *aImageNameInfo = [aImageName componentsSeparatedByString:@"_"];
-------------------------------------------------------------------------NSString-------------------------------------------------------------------------------
-------------------------------------------------------------------------NSMutableString-------------------------------------------------------------------------------
1:NSMutableString 字符串替换
NSMutableString *muStrHTML = [NSMutableString stringWithString:_detailsItem.html]; NSRange range = NSMakeRange(0, [muStrHTML length]); [muStrHTML replaceOccurrencesOfString:@"a" withString:@"b" options:NSCaseInsensitiveSearch range:range];
NSCaseInsensitiveSearch 表示不区分大小写进行替换
