#Nodejs buffer to string zip file#
#Nodejs buffer to string code#
#Nodejs buffer to string zip#

#Nodejs buffer to string zip#

Ignore the notes about compression in that other answer because your data is already ZIP compressed. Something better than Base64 for prior discussion on this topic. One such popular option is Base64 though it isn't super efficient (size wise), but it is better than many others. Now that you explain you're trying to store it in localStorage, then you need to encode the binary into a string format.

#Nodejs buffer to string zip file#

docX file, you probably need to actually parse it from it's binary ZIP file form into the actual components of the file in their appropriate format. If you want to do something useful with the. Your question doesn't describe what you're actually trying to accomplish. That is not what it does and that's why it doesn't do what you are expecting.

#Nodejs buffer to string code#

So, the code you show in your question is wrongly assuming that Buffer.toString() takes binary data and reversibly encodes it as a UTF8 string. If encoding is 'utf8' and a byte sequence in the input is not valid UTF-8, then each invalid byte is replaced with the replacement character U+FFFD. What Buffer.toString() does is take a Buffer that is ALREADY encoded in UTF-8 and puts it into a Javascript string. Your binary data will likely encounter things that are invalid in UTF-8 and those will be discarded or coerced into valid UTF-8, causing an irreversible change. toString() on it, you're assuming it is already encoding as UTF-8 in the buffer and you want to now move it into a Javascript string. docXfile is not a UTF-8 string (it's a binary ZIP file) so when you read it into a Buffer object and then call. So that means any change we do in either buffer will be reflected onto the other one.A. The package not only converts the buffer to ‘utf8’ string but also it converts the buffer to many forms like base64 encoded string, a hex-encoded string that we use in many contexts. When we apply a slice operation on a buffer, e.g., buf.slice(]), it also returns a new buffer, but the new buffer references the same memory as the original (just offset and cropped by the start and end indices). There is an NPM package called arraybuffer-to-string used to decode array buffers in actual strings. After slice, both the arrays will have different references (i.e., they do not share the memory, so whatever we change in either of the arrays will not affect the other one).īut this is not the case with a buffer. Slice on an array gives us a new array with sliced elements from beginning index to end index from the original array. Let’s say we want to apply a slice operation on the array arr.slice(]).

But there are some differences when we use these methods on buffer.

Just like arrays and strings, for buffer, we can use operations like slice, indexOf, and many others. It is because the String is counting characters based on UTF-8 encoding, and the buffer is counting the actual number of bytes used to represent the given string. Writes string to the buffer at offset using the given encoding. Syntax for Encoding string to base64 value: let base64Val om(value).toString('base64') Syntax for Decoding base64 value to string object: let decodedVal om(base64Val, 'base64').toString('ascii') Example of Encoding to. Now, as you can see, despite the length property behaving the same for String as it does for buffer, we are getting different answers. Buffer in Node.js can be used for encoding string into base64 value and also to decode into string. In order to protect our sensitive information we need to prefill this buffer and we do that by using the fill() method. We can see that there is some information left in our buffer which comes directly from our memory. As there is no initialization involved while creating the buffer, this method is faster than the Buffer.alloc(). That means it can contain some old or sensitive data out of your memory. Buffer.allocUnsafe()īuffer.allocUnsafe takes in size as an argument and returns a new buffer that is noninitialized. Here we have an 8-byte buffer, and every bit is prefilled with 0. There are three most used ways to create buffers:īom is used to create a buffer from either an array, a string, or from a buffer itself.īom(‘Node.js’) outputs Buffer.alloc()īuffer.alloc takes a size (integer) as an argument and returns a new initialized buffer of the specified size (i.e., it creates a filled buffer of a certain size).