Question

我需要将sql转换为c＃：基于字符串长度的人类可读字符串截断

请帮我将bellow sql代码转换为c＃

DECLARE @String     VARCHAR(MAX),
        @Size       TINYINT

SELECT @String = 
       'Hello my name is Jeff. I need some help on a project because right now this is how the application i am working with displays data.',
       @Size = 30

;WITH Peso(Part, StartPos, SIZE)
     AS (
         SELECT 1,
                1,
                CAST(
                    @Size - CHARINDEX(
                        ' ',
                        REVERSE(LEFT(SUBSTRING(@String, 1, @Size) + ' ', @Size))
                    ) AS INT
                )

         UNION ALL

         SELECT Part + 1,
                StartPos + SIZE + 1,
                CAST(
                    @Size - CHARINDEX(
                        ' ',
                        REVERSE(
                            LEFT(
                                SUBSTRING(@String, StartPos + SIZE + 1, @Size) + 
                                ' ',
                                @Size
                            )
                        )
                    ) AS INT
                )
         FROM   Peso
         WHERE  StartPos + SIZE <= DATALENGTH(@String)
     )

SELECT Part,
       SUBSTRING(@String, StartPos, SIZE)
FROM   Peso
ORDER BY Part

原始代码来自：http://weblogs.sqlteam.com/peterl/archive/2009/03/18/Human-readable-string-truncation.aspx

Answer 1

我无法将其从sql转换为c＃，因此，我编写了另一个代码：

public static IEnumerable<string> Split(string str, int chunkSize)
    {
        var list = str.Split(' ').ToList();
        var buildList = new List<string>();

        foreach (var s in list)
        {
            if (s.Length > chunkSize)
            {
                var x = SplitString(s, chunkSize);

                buildList.AddRange(x);
            }
            else
            {
                buildList.Add(s);
            }
        }

        var strResult = new List<string>();
        for (int i = 0; i < buildList.Count; i++)
        {
            strResult.Add("");
        }
        int line = 0;
        for (int i = 0; i < buildList.Count; i++)
        {
            if ((strResult[line] + " " + buildList[i]).Length > chunkSize + 1)
            {
                line++;
                strResult[line] = buildList[i].Trim();
            }
            else
            {
                strResult[line] = (strResult[line] + " " + buildList[i]).Trim();
            }
        }

        return strResult.Where(x => !string.IsNullOrEmpty(x)).ToList();
    }

    public static IEnumerable<string> SplitString(string str, int chunkSize)
    {
        return str.Select((x, i) => i)
          .Where(i => i % chunkSize == 0)
          .Select(i => str.Substring(i, str.Length - i >= chunkSize ? chunkSize : str.Length - i));
    }

并使用如下：

string text = "Hel l33 3333333333333333333933 3333333333313333333333333333333335 ause right now this is how the application i am working with displays data.";

var ret = string.Join(Environment.NewLine, Split(text, 30));

快乐的编码！

将sql转换为c＃：基于字符串长度的人类可读字符串截断

1 个答案: