Instructions for using the buffer.Buffer.byteLength method in node.js_node.js

Method description:

Get the byte length of the string.

The difference between this function and String.prototype.length is that the latter returns the number of characters in the string.

Grammar:

Copy code The code is as follows:

Buffer.byteLength(string, [encoding])

Receive parameters:

string character creation
encoding String encoding, the default is ‘utf8′

Example:

Copy code The code is as follows:

str = 'u00bd u00bc = u00be';
console.log(str ": " str.length " characters, "
Buffer.byteLength(str, 'utf8') " bytes");
// ½ ¼ = ¾: 9 characters, 12 bytes

Source code:

Copy code The code is as follows:

Buffer.byteLength = function(str, enc) {
var ret;
str = str '';
switch (enc) {
case 'ascii':
case 'binary':
case 'raw':
ret = str.length;
        break;
case 'ucs2':
case 'ucs-2':
case 'utf16le':
case 'utf-16le':
ret = str.length * 2;
        break;
case 'hex':
ret = str.length >>> 1;
        break;
Default:
ret = internal.byteLength(str, enc);
}
Return ret;
};