Node.js process.hasUncaughtExceptionCaptureCallback() 方法

process.hasUncaughtExceptionCaptureCallback() 方法是进程模块的内置应用程序编程接口，用于获取是否使用 process.setUncaughtExceptionCaptureCallback() 方法设置了回调。

句法：

process.hasUncaughtExceptionCaptureCallback()

参数：此方法不接受任何参数。
返回值：它返回一个布尔值，指定是否使用 process.setUncaughtExceptionCaptureCallback() 设置了回调。

下面的例子说明了在 Node.js 中process.hasUncaughtExceptionCaptureCallback() 方法的使用：

示例 1：

Javascript

// Node.js program to demonstrate the   
// process.hasUncaughtExceptionCaptureCallback() Method
  
// Include process module
const process = require('process');
  
console.log(process.hasUncaughtExceptionCaptureCallback());
  
// Printing whether a callback is set or not
if(process.hasUncaughtExceptionCaptureCallback()) {
    console.log("A callback has been set using "
    + "process.setUncaughtExceptionCaptureCallback() method");
}else{
        console.log("No callback has been set using "
        + "process.setUncaughtExceptionCaptureCallback() method");
}

输出：

false
No callback has been set using process.setUncaughtExceptionCaptureCallback() method

示例 2：

Javascript

// Node.js program to demonstrate the   
// process.hasUncaughtExceptionCaptureCallback() Method
  
// Include process module
const process = require('process');
   
function to_be_called(ex){
    console.log(ex);
}
  
// Setting callback 
process.setUncaughtExceptionCaptureCallback(to_be_called);
   
console.log(process.hasUncaughtExceptionCaptureCallback());
  
// Printing whether a callback is set or not
if(process.hasUncaughtExceptionCaptureCallback()){
    console.log("A callback has been set using "
    + "process.setUncaughtExceptionCaptureCallback() method");
}else{
    console.log("No callback has been set using "
    + "process.setUncaughtExceptionCaptureCallback() method");
}

输出：

true
A callback has been set using process.setUncaughtExceptionCaptureCallback() method

注意：上面的程序将使用 node filename.js 命令编译和运行。
参考： https://nodejs.org/api/process.html#process_process_hasuncaughtexceptioncapturecallback