Node.js Stream writable.destroyed 属性
writable.destroyed 属性是 Stream 模块的内置应用程序编程接口,用于检查 writable.destroy() 方法是否被调用。
句法:
writable.destroyed
返回值:如果 writable.destroy() 方法在它之前被调用,则此属性返回 true,否则返回 false。
以下示例说明了 Node.js 中writable.destroyed 属性的使用:
示例 1:
// Node.js program to demonstrate the
// writable.distroyed Property
// Accessing stream module
const stream = require('stream');
// Creating a stream and creating
// a write function
const writable = new stream.Writable({
// Write function with its
// parameters
write: function(chunk, encoding, next) {
// Converting the chunk of
// data to string
console.log(chunk.toString());
next();
}
});
// Writing data
writable.write('hi');
// Again writing some data
writable.write('hello');
// Calling destroy function
writable.destroy();
// Calling the Property
writable.destroyed;
输出:
hi
hello
true
示例 2:
// Node.js program to demonstrate the
// writable.distroyed Property
// Accessing stream module
const stream = require('stream');
// Creating a stream and creating
// a write function
const writable = new stream.Writable({
// Write function with its
// parameters
write: function(chunk, encoding, next) {
// Converting the chunk of
// data to string
console.log(chunk.toString());
next();
}
});
// Writing data
writable.write('hi');
// Again writing some data
writable.write('hello');
// Calling the Property
writable.destroyed;
输出:
hi
hello
false
在上面的示例中,输出为 false,因为在调用属性 writable.destroyed 之前未调用writable.destroy()方法。
参考: https://nodejs.org/api/stream.html#stream_writable_destroyed