how to throw error in javascript 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 how to raise the error

if (..condition..) {
    throw 'Error message';
  }

Example 4: javascript try

var someNumber = 1;
try {
  someNumber.replace("-",""); //You can't replace a int
} catch(err) {
 console.log(err);
}

Example 5: js errors

JS Errors
try
Lets you define a block of code to test for errors
catch
Set up a block of code to execute in case of an error
throw
Create custom error messages instead of the standard JavaScript errors
finally
Lets you execute code, after try and catch, regardless of the result

Example 6: javascript throw new error

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