javascript throw new error code example

Example 1: js throw error

throw new Error('Whoops!')

Example 2: node js throw error

FactoryController.prototype.create = function (callback) {
    //The throw is working, and the exception is returned.
    throw new Error('An error occurred'); //outside callback 
    try {
        this.check(function (check_result) {
            callback(check_result);
        });
    } catch (ex) {
        throw new Error(ex.toString());
    }
}

FactoryController.prototype.create = function (callback) {
    try {
        this.check(function (check_result) {
            //The throw is not working on this case to return the exception to the caller(parent)
            throw new Error('An error occurred'); //inside callback 
        });
    } catch (ex) {
        throw new Error(ex.toString());
    }
}

Example 3: javascript throw new error

throw new Error("Error message here"); // Uncaught Error: Error message here

Example 4: js errors

JS Error Name Values:
name
Sets or returns the error name
message
Sets or returns an error message in string from
EvalError
An error has occurred in the eval() function
RangeError
A number is “out of range”
ReferenceError
An illegal reference has occurred
SyntaxError
A syntax error has occurred
TypeError
A type error has occurred
URIError
An encodeURI() error has occurred

Example 5: javascript string error

Error.prototype.toString = function() {
  'use strict';

  var obj = Object(this);
  if (obj !== this) {
    throw new TypeError();
  }

  var name = this.name;
  name = (name === undefined) ? 'Error' : String(name);

  var msg = this.message;
  msg = (msg === undefined) ? '' : String(msg);

  if (name === '') {
    return msg;
  }
  if (msg === '') {
    return name;
  }

  return name + ': ' + msg;
};

Example 6: js throw new error

throw new Error("message");