Getting string with one char repeated in c# easy way

I want easy function like that:

string getStringWithCharAndLength(char ch, int l)
{
  //Some easy code
  //return ch+ch+...+ch(string with Length l)
}

Example:

string str = getStringWithCharAndLength('k',5);<br>
Console.WriteLine(str);// "kkkkk"

Note: not this kind of solution:

string getStringWithCharAndLength(char ch, int l)
{
   string str="";
   for(int i=0;i<l;i++)
      str+=ch;
   return str;
}