Grab the return value and get out of forEach in JavaScript? [duplicate]

Answer 1

instead of fields.forEach you can use fields.map. here is an example:

var source=[1,2,3,4,5];

var destination=source.map(function(item){
 if(item==3)
     return 'OUTPUT';
}).filter(function(item){return item;})[0];

console.log(destination); // prints 'OUTPUT'

Answer 2

Use return statement where you want to break-out like below.

[1, 2, 3, 4, 5, 6].forEach(function(value){
  if(value > 2) return; 
  console.log(value)
});

Answer 3

Use a good old vanilla for loop:

function discoverDependentFields(fields) {
  for (var fieldIndex = 0; fieldIndex < fields.length; fieldIndex ++) {
    var field = fields[fieldIndex];

    if (field.DependencyField) {
      var foundFields = fields.filter(function(fieldToFind) {
        return fieldToFind.Name === field.DependencyField;
      });
      if (foundFields.length === 1) {
        return foundFields[0];
      }
    }
  }
}

Well, if you want to stay fancy, use filter again:

function discoverDependentFields(fields) {
  return fields.filter(function(field) {
    if (field.DependencyField) {
      var foundFields = fields.filter(function(fieldToFind) {
        return fieldToFind.Name === field.DependencyField;
      });
      if (foundFields.length === 1) {
        return foundFields[0];
      }
    }
  })[0];
}