Instructions for using the fs.exists method in node.js_node.js

Method description:

Test whether a file under a certain path exists.

The callback function contains a parameter exists, true if the file exists, otherwise false.

Grammar:

Copy code The code is as follows:

fs.exists(path, callback)

Since this method belongs to the fs module, the fs module needs to be introduced before use (var fs= require(“fs”) )

Receive parameters:

path file path to be detected

callback callback

Example:

Copy code The code is as follows:

fs.exists('/etc/passwd', function (exists) {
util.debug(exists ? "it's there" : "no passwd!");
});

Source code:

Copy code The code is as follows:

fs.exists = function(path, callback) {
if (!nullCheck(path, cb)) return;
binding.stat(pathModule._makeLong(path), cb);
function cb(err, stats) {
If (callback) callback(err ? false : true);
}
};