删除字符串中的最后一个换行符

Question

I have a list of names (var names) which after running some other code to add or remove names, I want to place in a list called nameupdated:

var names = new Array('Alice', 'Bryan', 'Catherine', 'Douglas', 'Emma', 'Frank'); 
var name = "";
var nameupdated = "";
var text = "";

for(var i in names){
name = names[i];
  if (name == "" || name == text || typeof(name) == undefined)
  {

  }
  else{
    nameupdated = nameupdated + name + "\n";
  }
}

I can't seem to remove the last line break however I tried to manipulate the code. Anyone with any ideas how?

Answer 1

The logic will probably be a lot clearer if you use .filter to remove the items you want to exclude, followed by .join by newlines. Note that array literals are generally nicer to work with than using the new Array constructor:

 var text = 'foo'; var names = [ 'Alice', 'Bryan', 'Catherine', 'Douglas', 'Emma', 'Frank' ]; var nameUpdated = names .filter(name => !(name == "" || name == text || typeof(name) == undefined)) .join('\\n'); console.log(nameUpdated); 

Answer 2

1. Try first If you want to remove last line break then you can do it in one line.
2. Try second if you want string with new line

 var names = [ 'Alice', 'Bryan', 'Catherine', 'Douglas', 'Emma', 'Frank' ]; //Array with \\n var result = [...names].map((d, i) => i < names.length-1 && (name => !(name == "" || name == text || typeof(name) == undefined)) ? d+'\\n' : d); //String with new line after each element var result1 = [...names].map((d, i) => i < names.length-1 && (name => !(name == "" || name == text || typeof(name) == undefined))? d+'\\n' : d).join(''); console.log(result); console.log(result1);