有没有一种简单的方法可以将字符串重复X次？

#1 楼

string result = new String('-', 5);
Output: -----

#2 楼

#3 楼

string result = new StringBuilder().Insert(0, "---", 5).ToString();

#4 楼

public static class StringExtensions
{
    public static string Repeat(this string input, int count)
    {
        if (!string.IsNullOrEmpty(input))
        {
            StringBuilder builder = new StringBuilder(input.Length * count);

            for(int i = 0; i < count; i++) builder.Append(input);

            return builder.ToString();
        }

        return string.Empty;
    }
}

#5 楼

#6 楼

#7 楼

String.Concat(Enumerable.Repeat("---", 5))

#8 楼

public static string Repeat(this string str, int count)
{
    return Enumerable.Repeat(str, count)
                     .Aggregate(
                        new StringBuilder(),
                        (sb, s) => sb.Append(s))
                     .ToString();
}

#9 楼

        string indent = "---";
        string n = string.Concat(Enumerable.Repeat(indent, 1).ToArray());
        string n = string.Concat(Enumerable.Repeat(indent, 2).ToArray());
        string n = string.Concat(Enumerable.Repeat(indent, 3).ToArray());

#10 楼

"".PadLeft(3*Indent,'-')

int Indent = 2;
        
string[] sarray = new string[6];  //assuming max of 6 levels of indent, 0 based

for (int iter = 0; iter < 6; iter++)
{
    //using c0rd's stringbuilder concept, insert ABC as the indent characters to demonstrate any string can be used
    sarray[iter] = new StringBuilder().Insert(0, "ABC", iter).ToString();
}

Console.WriteLine(sarray[Indent] +"blah");  //now pretend to output some indented line

#11 楼

public static IEnumerable<T> Repeat<T>(this IEnumerable<T> source, int times)
{
    source = source.ToArray();
    return Enumerable.Range(0, times).SelectMany(_ => source);
}

#12 楼

public static string Repeat(this string @this, int count)
{
    var dest = new char[@this.Length * count];
    for (int i = 0; i < dest.Length; i += 1)
    {
        dest[i] = @this[i % @this.Length];
    }
    return new string(dest);
}

#13 楼

int indentCount = 3;
string indent = "---";
string stringToBeIndented = "Blah";
// Need dummy char NOT in stringToBeIndented - vertical tab, anyone?
char dummy = '\v';
stringToBeIndented.PadLeft(stringToBeIndented.Length + indentCount, dummy).Replace(dummy.ToString(), indent);

#14 楼

#15 楼

Console.Write(new string('=', 30) + "\n");

#16 楼

    public static string Repeat_CharArray_LogN(this string str, int times)
    {
        int limit = (int)Math.Log(times, 2);
        char[] buffer = new char[str.Length * times];
        int width = str.Length;
        Array.Copy(str.ToCharArray(), buffer, width);

        for (int index = 0; index < limit; index++)
        {
            Array.Copy(buffer, 0, buffer, width, width);
            width *= 2;
        }
        Array.Copy(buffer, 0, buffer, width, str.Length * times - width);

        return new string(buffer);
    }

#17 楼

public static string Repeat(this string text, int count)
{
    if (!String.IsNullOrEmpty(text))
    {
        return String.Concat(Enumerable.Repeat(text, count));
    }
    return "";
}

#18 楼

//Strings and chars ver 1
string.Join("", Enumerable.Repeat("text" , 2 ));    //result: texttext

//Strings and chars ver 2
new StringBuilder().Insert(0, "text", 2).ToString(); //result: texttext

// Chars only:
'5' * 3; //result: 555

public static class RepeatExtensions
{
    //extension with owerride Multiply is impossible so...
    //also works faster than .Insert(0,x,y) - may be important for web
    public static string Repeat(this string str, int times)
    {
        var a = new StringBuilder();

        ( () => a.Append(str) ).RepeatAction(times) ;
        
        return a.ToString();
    }

    public static void RepeatAction(this Action action, int count)
    {
        for (int i = 0; i < count; i++)
        {
            action();
        }
    }
}

 var a = "Hello".Repeat(3); //result: HelloHelloHello

#19 楼

public static void PrintFigure(int shapeSize)
{
    string figure = "\/";
    for (int loopTwo = 1; loopTwo <= shapeSize - 1; loopTwo++)
    {
        Console.Write($"{figure}");
    }
}

#20 楼

public static class StringExtension
{
  public static string Repeat(this string str, int count)
  {
    string ret = "";

    for (var x = 0; x < count; x++)
    {
      ret += str;
    }

    return ret;
  }
}

public static class StringExtension
{
  public static string Repeat(this string str, int count)
  {
    if (count == 0)
      return "";

    return string.Concat(Enumerable.Repeat(indent, N))
  }
}