網上的Base64解碼器

NSString *value = @"PFJlc3BvbnNlIHhtbG5zPSJ1cm46b2FzaXM6bmFtZXM6dGM6U0FNTDoyLjA6cHJvdG9jb2wiIERlc3RpbmF0aW9uPSJodHRwczovL2RlbW8uZWZtZm0uY29tL3NhbWwvU1NPIiBJRD0iX2M3ZTQ2YjdiOGE0YjFlZTFmYjI2MGYyYzY3ZTFlNTQ1NWIwOCIgSW5SZXNwb25zZVRvPSJhNTY4YWhhNWM"

I've tried :

NSData *decodedData = [[NSData alloc] initWithBase64EncodedString:value options:0];NSString *decodedString = [[NSString alloc] initWithData:decodedData encoding:NSUTF8StringEncoding];NSLog(@"Decode String Value: %@", decodedString);

But I get Null. Please help

Before you downvote the question, please see that I've tried the link which you've mentioned. But unfortunately it is not decoding my string.

I have a problem with Base64 encoding/decoding. I have google chrome extension which scraps some simple data from opened web page like title, URL, image and then I am doing encoding of all these data and sending them to my nodejs app route.

The problem happens when some time in node router Base64 decode removes 'r' char from web page URL.

Here is my code in chrome extension which doing a encoding:

var Base64={_keyStr:"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+=",encode:function(e){var t="";var n,r,i,s,o,u,a;var f=0;e=Base64._utf8_encode(e);while(f<e.length){n=e.charCodeAt(f++);r=e.charCodeAt(f++);i=e.charCodeAt(f++);s=n>>2;o=(n&3)<<4|r>>4;u=(r&15)<<2|i>>6;a=i&63;if(isNaN(r)){u=a=64}else if(isNaN(i)){a=64}t=t+this._keyStr.charAt(s)+this._keyStr.charAt(o)+this._keyStr.charAt(u)+this._keyStr.charAt(a)}return t},decode:function(e){var t="";var n,r,i;var s,o,u,a;var f=0;e=e.replace(/[^A-Za-z0-9+/=]/g,"");while(f<e.length){s=this._keyStr.indexOf(e.charAt(f++));o=this._keyStr.indexOf(e.charAt(f++));u=this._keyStr.indexOf(e.charAt(f++));a=this._keyStr.indexOf(e.charAt(f++));n=s<<2|o>>4;r=(o&15)<<4|u>>2;i=(u&3)<<6|a;t=t+String.fromCharCode(n);if(u!=64){t=t+String.fromCharCode(r)}if(a!=64){t=t+String.fromCharCode(i)}}t=Base64._utf8_decode(t);return t},_utf8_encode:function(e){e=e.replace(/rn/g,"n");var t="";for(var n=0;n<e.length;n++){var r=e.charCodeAt(n);if(r<128){t+=String.fromCharCode(r)}else if(r>127&&r<2048){t+=String.fromCharCode(r>>6|192);t+=String.fromCharCode(r&63|128)}else{t+=String.fromCharCode(r>>12|224);t+=String.fromCharCode(r>>6&63|128);t+=String.fromCharCode(r&63|128)}}return t},_utf8_decode:function(e){var t="";var n=0;var r=c1=c2=0;while(n<e.length){r=e.charCodeAt(n);if(r<128){t+=String.fromCharCode(r);n++}else if(r>191&&r<224){c2=e.charCodeAt(n+1);t+=String.fromCharCode((r&31)<<6|c2&63);n+=2}else{c2=e.charCodeAt(n+1);c3=e.charCodeAt(n+2);t+=String.fromCharCode((r&15)<<12|(c2&63)<<6|c3&63);n+=3}}return t}}var posturl1 = Base64.encode(posturl);

And this is my code in Nodejs router which doing Base64 decoding:

    var Base64={_keyStr:"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+=",encode:function(e){var t="";var n,r,i,s,o,u,a;var f=0;e=Base64._utf8_encode(e);while(f<e.length){n=e.charCodeAt(f++);r=e.charCodeAt(f++);i=e.charCodeAt(f++);s=n>>2;o=(n&3)<<4|r>>4;u=(r&15)<<2|i>>6;a=i&63;if(isNaN(r)){u=a=64}else if(isNaN(i)){a=64}t=t+this._keyStr.charAt(s)+this._keyStr.charAt(o)+this._keyStr.charAt(u)+this._keyStr.charAt(a)}return t},decode:function(e){var t="";var n,r,i;var s,o,u,a;var f=0;e=e.replace(/[^A-Za-z0-9+/=]/g,"");while(f<e.length){s=this._keyStr.indexOf(e.charAt(f++));o=this._keyStr.indexOf(e.charAt(f++));u=this._keyStr.indexOf(e.charAt(f++));a=this._keyStr.indexOf(e.charAt(f++));n=s<<2|o>>4;r=(o&15)<<4|u>>2;i=(u&3)<<6|a;t=t+String.fromCharCode(n);if(u!=64){t=t+String.fromCharCode(r)}if(a!=64){t=t+String.fromCharCode(i)}}t=Base64._utf8_decode(t);return t},_utf8_encode:function(e){e=e.replace(/rn/g,"n");var t="";for(var n=0;n<e.length;n++){var r=e.charCodeAt(n);if(r<128){t+=String.fromCharCode(r)}else if(r>127&&r<2048){t+=String.fromCharCode(r>>6|192);t+=String.fromCharCode(r&63|128)}else{t+=String.fromCharCode(r>>12|224);t+=String.fromCharCode(r>>6&63|128);t+=String.fromCharCode(r&63|128)}}return t},_utf8_decode:function(e){var t="";var n=0;var r=c1=c2=0;while(n<e.length){r=e.charCodeAt(n);if(r<128){t+=String.fromCharCode(r);n++}else if(r>191&&r<224){c2=e.charCodeAt(n+1);t+=String.fromCharCode((r&31)<<6|c2&63);n+=2}else{c2=e.charCodeAt(n+1);c3=e.charCodeAt(n+2);t+=String.fromCharCode((r&15)<<12|(c2&63)<<6|c3&63);n+=3}}return t}}  var url = Base64.decode(decodedurl);

This is a sample of a problem:I am encoding this url and some other data (title, imagepath from page and url) http://www.c-sharpcorner.com/article/angularjs-2-0-from-beginning-introduction-of-angular-js-2-0/

This is result of encoding an nodejs router: http://www.c-sharpconer.com/article/angularjs-2-0-from-beginning-introduction-of-angular-js-2-0/

Decoded url missing 'r' charachter in domain name c-sharpconer shuld be c-sharpcoRner

I am trying to first select pdf file, then encode it to base64 and save it to shared preference. After that, decode and save to pdf. And open that pdf to view.

When opening it displays message "This document cannot be opened". It looks like there was some problem on encoding/decoding part. I don't know where. So, if anyone has idea on it, It would be great help for me. Thanks,

My code is as follows:

Encoding :

public static String getBase64Pdf(String pdfFilePath){    try{        InputStream inputStream = new FileInputStream(pdfFilePath);        byte[] byteArray = IOUtils.toByteArray(inputStream);        String encodedPdfString = Base64.encodeToString(byteArray, Base64.DEFAULT);        PrintLog.showTag(TAG,"pdf converted to string : " + encodedPdfString);        return encodedPdfString;    }catch (IOException e){    }    return "";}

Decoding, saving to file and open pdf :

private void openPdfViewer(){    try{        PrintLog.showTag(TAG,"== opnPdfViewer & length of base64 string is =="                + sessionManager.getBase64ProofImage().length());        //== decode and write file here        String base64pdf = sessionManager.getBase64ProofImage();//gets base64 from shared preference        final File newFilePath = new File(getActivity().getFilesDir(), "warrantyProof.pdf");        byte[] pdfAsBytes = Base64.decode(base64pdf, Base64.NO_WRAP);        FileOutputStream os;        os = new FileOutputStream(newFilePath, false);        os.write(pdfAsBytes);        os.flush();        os.close();        //==== open pdf file here        File file = new File(getActivity().getFilesDir(),"warrantyProof.pdf");        Intent intent = new Intent(Intent.ACTION_VIEW);        intent.setDataAndType(Uri.fromFile(file), "application/pdf");        intent.setFlags(Intent.FLAG_ACTIVITY_NO_HISTORY);        startActivity(intent);    }catch (IOException e){        PrintLog.showException(TAG,"IO exception saving pdf ",e);    }    catch (Exception e){        PrintLog.showException(TAG,"exception opening pdf",e);    }}

A library save a token as Data in UserDefaults

//loading the tokenif let token = UserDefaults.standard.object(forKey: "token") as? Data { let base64Encoded = token.base64EncodedData let base64EncodedString = token.base64EncodedString()}

When I print that base64Encoded value in the console I get the value: Y2E2N2Y5NTItNDVkOC00YzZkLWFkZDMtZGRiMjc5NGE3YWI2OjdmZDU1ZTAyLWExMjEtNGQ1ZC05N2MzLWM5OWY4NTg5NTIzNg== as Data

When I copy this value from the output in the console and use this website https://www.base64decode.org/ I got the expected result. ca67f952-45d8-4c6d-add3-ddb2794a7ab6:7fd55e02-a121-4d5d-97c3-c99f85895236

My problem is that I don't get convert that base64Encoded to String in my code.

When I use base64EncodedString I got a string, but I can't figure out which format this is: PFsYdirs21247rRG/XcWOVGUGUcCCTzXz7VFAnunLJU= The method base64EncodedString() This is an method from Apple: https://developer.apple.com/documentation/foundation/nsdata/1413546-base64encodedstring

When I decode this value to utf8 at the website I got: <[v*]Fw9QG

When I try to convert my base64Encoded (Data, not String) to a string like this

if let toString = String(data: base64Encoded, encoding: String.Encoding.utf8) as String { print("test \(toString)")}

my compiler threw an error: Cannot convert value of type(Data.Base64EncodingOptions) -> Data to expected argument type Data

Here I found a solution to decode when my Data-value would be a string.
https://stackoverflow.com/a/31859383/4420355

So I'm quite confused about the results. Long story short:

I have base64Encoded Data (Y2E2N2Y5NTItNDVkOC00YzZkLWFkZDMtZGRiMjc5NGE3YWI2OjdmZDU1ZTAyLWExMjEtNGQ1ZC05N2MzLWM5OWY4NTg5NTIzNg==) and want them convert to an utf8 string. I don't get handle this.

I have a string that I found, that is probably hashed in base64. Decoding it returns error characters in every encoding I've tried. I also can't access the code that generated it and can't reverse engineer it.

This is the base64:AAECAR8GxwPJBLsFmQfZB/gIDI0B2AGoArUDhwSSBe0G6wfbCe0JgQr+DAA=

Now, its 60 byte long, and all the characters are valid for base64, if you have a better guess than base64 inform me!

I also have converted it into a byte array, but I don't really know how to convert the byte array to a string with different encoding. Maybe I could run a for each loop that prints the resulting string in different encodings, till I find one that is the actual text?