Question

在Objective-C扩展名之前为文件名添加后缀的最简单方法是什么？

示例

原名：image.png
后缀：~ipad
结果：image~ipad.png

Answer 1

NSString有一大堆与路径相关的方法：

NSString * appendSuffixToPath(NSString * path, NSString * suffix) {
    NSString * containingFolder = [path stringByDeletingLastPathComponent];
    NSString * fullFileName = [path lastPathComponent];
    NSString * fileExtension = [fullFileName pathExtension];
    NSString * fileName = [fullFileName stringByDeletingPathExtension];
    NSString * newFileName = [fileName stringByAppendingString:suffix];
    NSString * newFullFileName = [newFileName stringByAppendingPathExtension:fileExtension];

    return [containingFolder stringByAppendingPathComponent:newFullFileName];
}

（是的，你可以用很少的变量做到这一点，但我想说清楚每个方法在做什么）

Answer 2

知道它已经老了但是有人可能会喜欢这个Swift解决方案

extension String {
func appendSuffixBeforeExtension(suffix: String) -> String {
        let regex = NSRegularExpression(pattern: "(\\.\\w+$)", options: nil, error: nil)
        return regex!.stringByReplacingMatchesInString(self, options: nil, range: NSMakeRange(0, count(self)), withTemplate: "\(suffix)$1")
    }
}

然后这样称呼它

let mytxt = "/somepath/file.jpg"
let retina = mytxt.appendSuffixBeforeExtension("@x2")

Answer 3

使用URL方法：

let suffixedFileURL = fileURL
    .deletingLastPathComponent()
    .appendingPathComponent(
        fileURL
            .deletingPathExtension()
            .lastPathComponent
            .appending("suffix")
    )
    .appendingPathExtension(fileURL.pathExtension)

Answer 4

上述解决方案不适用于文件名，例如../ filename.pvr.ccz

所以我稍微调整了一下来考虑多个文件扩展名：

-(NSString *)appendSuffixToPath:(NSString *)pPath withSuffix:(NSString *)pSuffix {
    NSString * containingFolder = [pPath stringByDeletingLastPathComponent];
    NSString * fullFileName = [pPath lastPathComponent];

    NSMutableArray *extensions = [[NSMutableArray alloc] init];
    NSString * fileExtension = [fullFileName pathExtension];
    [extensions addObject:fileExtension];

    NSString * fileName = [fullFileName stringByDeletingPathExtension];
    while([fileName pathExtension].length > 0){
        fileExtension = [fileName pathExtension];
        [extensions addObject:fileExtension];
        fileName = [fileName stringByDeletingPathExtension];
    }

    NSString * newFileName = [fileName stringByAppendingString:pSuffix];

    NSString * newFullFileName = newFileName;
    while ([extensions count] > 0) {
        newFullFileName = [newFullFileName stringByAppendingPathExtension:[extensions objectAtIndex:((int)[extensions count] - 1)]];
        [extensions removeObjectAtIndex:((int)[extensions count] - 1)];
    }

    NSString *result = [containingFolder stringByAppendingPathComponent:newFullFileName];
    return result;
}

在扩展名之前为文件名添加后缀

4 个答案: