如何将一组字符串分成C#中的组成字符?

时间:2013-05-30 20:05:11

标签: c# string algorithm

将字符串strArr中的单个字符分隔为这些字符charArr的数组的最佳方法是什么,如下所示?

string[] strArr = { "123", "456", "789" };
char[] chrArr = { '1', '2', '3', '4', '5', '6', '7', '8', '9' };

这就是我目前正在做的事情,但我认为它不是很优雅:

int characterCount = 0;

for (int i = 0; i < strArr.Length; i++)
{
    characterCount += strArr[i].Length;
}

int indexCount = 0;
char[] chrArr = new char[characterCount];

for (int i = 0; i < strArr.Length; i++)
{
    for (int j = 0; j < strArr[i].Length; j++)
    {
        chrArr[indexCount] = strArr[i][j];
        indexCount++;
    }
}

6 个答案:

答案 0 :(得分:42)

嗯,最简单的方式是:

char[] chrArr = string.Join(string.Empty, strArr).ToCharArray();

为了确保这里没有混淆性能特征,这是一个在LINQPad中测试的简短程序(不要忘记在右下角打开优化):

static string[] strArr = { "123", "456", "789" };

void Main()
{
    const int iterations = 10000000; // 10 million

    // Warm up JITter
    StringJoin();
    LINQSelectMany();
    LINQ();

    Stopwatch sw = Stopwatch.StartNew();
    for (int index = 0; index < iterations; index++)
        StringJoin();
    sw.Stop();
    sw.ElapsedMilliseconds.Dump("String.Join");

    sw.Restart();
    for (int index = 0; index < iterations; index++)
        LINQSelectMany();
    sw.Stop();
    sw.ElapsedMilliseconds.Dump("LINQ SelectMany");

    sw.Restart();
    for (int index = 0; index < iterations; index++)
        LINQ();
    sw.Stop();
    sw.ElapsedMilliseconds.Dump("LINQ");
}

public static void StringJoin()
{
    char[] c = string.Join(string.Empty, strArr).ToCharArray();
}

public static void LINQSelectMany()
{
    char[] c = strArr.SelectMany(s => s).ToArray();
}

public static void LINQ()
{
    var characters = (from s in strArr
                      from c in s
                      select c).ToArray();

}

如果您想使用它,可以下载此LINQPad脚本here

输出(以毫秒为单位):

String.Join 
765 

LINQ SelectMany 
5098 

LINQ 
5465 

(关于性能测量代码的常见警告适用于此处,指出我所犯的任何错误)

答案 1 :(得分:19)

我愿意:

char[] chrArr = strArr.SelectMany(s => s).ToArray();

答案 2 :(得分:7)

var res = strArr.SelectMany(c => c.ToCharArray()).ToArray();

答案 3 :(得分:3)

基于LINQ的版本将是:

var input = new string[] { "abc", "def", "ghi" };
var characters = (from s in input
                  from c in s
                  select c).ToArray();

foreach (var c in characters) Console.WriteLine(c);

答案 4 :(得分:1)

这基本上是Jesse Slicer回答的延伸。

只需使用ReSharper清理您的代码(如果您没有这样或类似的内容,请立即获取)产生以下结果:

var characterCount = strArr.Sum(t => t.Length);

var indexCount = 0;
var chrArr = new char[characterCount];

foreach (var t1 in strArr.SelectMany(t => t))
{
    chrArr[indexCount] = t1;
    indexCount++;
}

foreach只是填充一个数组,并且已经有一个LINQ方法ToArray。然后characterCountindexCount完全没必要。

var chrArr = strArr.SelectMany(t => t).ToArray();

答案 5 :(得分:0)

试试这个..

 string value="";
 string[] strArr = { "123", "456", "789" }; //Your string array.

 for(int i=0;i<strArr.Length;i++)
 {
     value+=strArr[i];
 }
  char [] array=value.ToCharArray();