JavaScript: Print all the methods in an JavaScript object

JavaScript Object: Exercise-11 with Solution

Print Object Methods

Write a JavaScript function to print all the methods in a JavaScript object.
Test Data:
console.log(all_properties(Array));
["length", "name", "arguments", "caller", "prototype", "isArray", "observe", "unobserve"]

Sample Solution:

JavaScript Code:

function FindAllMethods(obj) {
    return Object.getOwnPropertyNames(obj).filter(function(property) {
        return typeof obj[property] == "function";
    });
}
//above code finds methods only
//Following code finds both properties and methods 
console.log(FindAllMethods(Math));
console.log(FindAllMethods(Array));
function all_properties(obj) 
{
 return Object.getOwnPropertyNames(obj);
}

console.log(all_properties(Math));

console.log(all_properties(Array));

Output:

["abs", "acos", "acosh", "asin", "asinh", "atan", "atanh", "atan2", "ceil", "cbrt", "expm1", "clz32", "cos", "cosh", "exp", "floor", "fround", "hypot", "imul", "log", "log1p", "log2", "log10", "max", "min", "pow", "random", "round", "sign", "sin", "sinh", "sqrt", "tan", "tanh", "trunc"]
["isArray", "from", "of"]
["abs", "acos", "acosh", "asin", "asinh", "atan", "atanh", "atan2", "ceil", "cbrt", "expm1", "clz32", "cos", "cosh", "exp", "floor", "fround", "hypot", "imul", "log", "log1p", "log2", "log10", "max", "min", "pow", "random", "round", "sign", "sin", "sinh", "sqrt", "tan", "tanh", "trunc", "E", "LN10", "LN2", "LOG10E", "LOG2E", "PI", "SQRT1_2", "SQRT2"]
["length", "name", "prototype", "isArray", "from", "of"]

Flowchart:

Live Demo:

Click on the Codepen logo at the top right corner of the code snippet below to view the output.

See the Pen javascript-object-exercise-11 by w3resource (@w3resource) on CodePen.

For more Practice: Solve these Related Problems:

• Write a JavaScript function that extracts and prints all method names of a given object using Object.getOwnPropertyNames().
• Write a JavaScript function that lists only the methods defined directly on an object, excluding inherited ones.
• Write a JavaScript function that filters an object’s properties to display only those that are functions.
• Write a JavaScript function that recursively prints methods of an object along with the names of the objects in its prototype chain.

Improve this sample solution and post your code through Disqus.

Previous: Write a JavaScript program to sort an array of JavaScript objects.
Next: Write a JavaScript function to parse an URL.