js call function by name code example

Example 1: js call function by string name

function test() {
  console.log('Executed function "test".');
}

window['test']();

Example 2: javascript execute function by string name

//function to execute some other function by it's string name 
function executeFunctionByName(functionName, context , args ) {
  var args = Array.prototype.slice.call(arguments, 2);
  var namespaces = functionName.split(".");
  var func = namespaces.pop();
  for(var i = 0; i < namespaces.length; i++) {
    context = context[namespaces[i]];
  }
  return context[func].apply(context, args);
}

//my adding function, could be any function
function myAddFunction(a,b){
 return a+b;
}

//execute myAddFunction from string
var c=executeFunctionByName("myAddFunction", window, 3,4); //7

Example 3: javascript function name

function WriteSomeShitOut(){ 
  var a = new Error().stack.match(/at (.*?) /);
  console.log(a[1]);
} 
WriteSomeShitOut();

Example 4: function calls

const obj = {
  foo: 1,
  get bar() {
    return 2;
  }
};

let copy = Object.assign({}, obj); 
console.log(copy); 
// { foo: 1, bar: 2 }
// The value of copy.bar is obj.bar's getter's return value.

// This is an assign function that copies full descriptors
function completeAssign(target, ...sources) {
  sources.forEach(source => {
    let descriptors = Object.keys(source).reduce((descriptors, key) => {
      descriptors[key] = Object.getOwnPropertyDescriptor(source, key);
      return descriptors;
    }, {});
    
    // By default, Object.assign copies enumerable Symbols, too
    Object.getOwnPropertySymbols(source).forEach(sym => {
      let descriptor = Object.getOwnPropertyDescriptor(source, sym);
      if (descriptor.enumerable) {
        descriptors[sym] = descriptor;
      }
    });
    Object.defineProperties(target, descriptors);
  });
  return target;
}

copy = completeAssign({}, obj);
console.log(copy);
// { foo:1, get bar() { return 2 } }