To use append upload, you can use the AppendObject operation of OSS to directly append content to the append objects that are uploaded.

For more information about append upload, see Append upload.

The following code provides an example on how to use append upload:

OSSAppendObjectRequest * append = [OSSAppendObjectRequest new];
// Configure the required fields. bucketName indicates the name of the bucket. objectKey is equivalent to objectName that indicates the complete path of the object you want to upload to OSS by using append upload. The path must include the extension of the object. For example, you can set objectKey to abc/efg/123.jpg.
append.bucketName = @"<bucketName>";
append.objectKey = @"<objectKey>";
// Specify the starting position to append the object.
append.appendPosition = 0; 
NSString * docDir = [self getDocumentDirectory];
append.uploadingFileURL = [NSURL fileURLWithPath:@"<filepath>"];
// Configure the optional fields.
append.uploadProgress = ^(int64_t bytesSent, int64_t totalByteSent, int64_t totalBytesExpectedToSend) {
    NSLog(@"%lld, %lld, %lld", bytesSent, totalByteSent, totalBytesExpectedToSend);
};
// append.contentType = @"";
// append.contentMd5 = @"";
// append.contentEncoding = @"";
// append.contentDisposition = @"";
OSSTask * appendTask = [client appendObject:append];
[appendTask continueWithBlock:^id(OSSTask *task) {
    NSLog(@"objectKey: %@", append.objectKey);
    if (! task.error) {
        NSLog(@"append object success!") ;
        OSSAppendObjectResult * result = task.result;
        NSString * etag = result.eTag;
        long nextPosition = result.xOssNextAppendPosition;
    } else {
        NSLog(@"append object failed, error: %@" , task.error);
    }
    return nil;
}];

For more information about the optional fields, see AppendObject.