如何更改onDownloadStart中的字符串？

Question

在我的下载管理器下载文件之前，如何在文件名中用“_”和“/”符号替换“+”符号？

@Override
        public void onDownloadStart(String url, String userAgent,
                                    String contentDisposition, String mimeType,
                                    long contentLength) {
            DownloadManager.Request request = new DownloadManager.Request(
                    Uri.parse(url));
            request.setMimeType(mimeType);
            String cookies = CookieManager.getInstance().getCookie(url);
            request.addRequestHeader("cookie", cookies);
            request.addRequestHeader("User-Agent", userAgent);
            request.setDescription("Downloading file...");
            request.setTitle(URLUtil.guessFileName(url, contentDisposition,
                    mimeType));
            request.allowScanningByMediaScanner();
            request.setNotificationVisibility(DownloadManager.Request.VISIBILITY_VISIBLE_NOTIFY_COMPLETED);
            request.setDestinationInExternalPublicDir(
                    Environment.DIRECTORY_DOWNLOADS, URLUtil.guessFileName(
                            url, contentDisposition, mimeType));
            DownloadManager dm = (DownloadManager) getSystemService(DOWNLOAD_SERVICE);
            dm.enqueue(request);

Answer 1

让我们假设你的字符串/文件名是：

String myFileName = "basal_metabolic_rate+example.pdf";

您可以执行以下操作，将+替换为_：

String result = myFileName.replaceAll("[+]", "_");

字符串result现在将返回：

basal_metabolic_rate_example.pdf

当你想用“=”代替“/”时，你也可以这样做：

String myFileName = "basal/metabolic/rate/example.pdf";
String result = myFileName.replaceAll("[/]", "=");

// Your file will now be basal=metabolic=rate=example.pdf

修改

以下是在代码中实现它的方法：

@Override
public void onDownloadStart(String url, String userAgent, String contentDisposition, String mimeType, long contentLength) {

        //You can first get the filename:
        String filename = URLUtil.guessFileName(url, contentDisposition, mimeType);
        //Then you can replace the "+" with "_"
        String replacePlus = filename.replaceAll("[+]", "_");
        //Then you can replace the "/" with "="
        String replaceSlash = replacePlus.replaceAll("[/]", "=");

        DownloadManager.Request request = new DownloadManager.Request(
        Uri.parse(url));
        request.setMimeType(mimeType);
        String cookies = CookieManager.getInstance().getCookie(url);
        request.addRequestHeader("cookie", cookies);
        request.addRequestHeader("User-Agent", userAgent);
        request.setDescription("Downloading file...");

        //Now here where you set the title you can set it to the last edited string, like this:
        request.setTitle(replaceSlash);

        request.allowScanningByMediaScanner();
        request.setNotificationVisibility(DownloadManager.Request.VISIBILITY_VISIBLE_NOTIFY_COMPLETED);

        //And here where you set the destination directory
        request.setDestinationInExternalPublicDir(Environment.DIRECTORY_DOWNLOADS, replaceSlash);

        DownloadManager dm = (DownloadManager) getSystemService(DOWNLOAD_SERVICE);
        dm.enqueue(request);