Question

我有一个从数据库中取出的大文本字段

rs.Item("content")

如何将此限制为100个字符，但不能删除最后一个字。例如“将此限制为100 cha ...”

我想将...添加到最后。

由于

Answer 1

Console.WriteLine(content.Substring(content.IndexOf(" ", 99)) + "...");

Answer 2

我使用以下方法：

''' <summary>
''' Creates a shortend version of a string, with optional follow-on characters.
''' </summary>
''' <param name="stringToShorten">The string you wish to shorten.</param>
''' <param name="newLength">
''' The new length you want the string to be (nearest whole word).
''' </param>
''' <param name="isAbsoluteLength">
''' If set to <c>true</c> the string will be no longer than <i>newLength</i>.
''' and will cut off mid-word.
''' </param>
''' <param name="stringToAppend">
''' What you'd like on the end of the shorter string to indicate truncation.
''' </param>
''' <returns>The shorter string.</returns>
Public Shared Function ShortenString(stringToShorten As String, newLength As Integer, isAbsoluteLength As Boolean, stringToAppend As String) As String
  If Not isAbsoluteLength AndAlso (newLength + stringToAppend.Length > stringToShorten.Length) Then
    ' requested length plus append will be longer than original
    Return stringToShorten
  ElseIf isAbsoluteLength AndAlso (newLength - stringToAppend.Length > stringToShorten.Length) Then
    ' requested length minus append will be longer than original
    Return stringToShorten
  Else
    Dim cutOffPoint As Integer

    If Not isAbsoluteLength Then
      ' Find the next space after the newLength.
      cutOffPoint = stringToShorten.IndexOf(" ", newLength)
    Else
      ' Just cut the string off at exactly the length required.
      cutOffPoint = newLength - stringToAppend.Length
    End If

    If cutOffPoint <= 0 Then
      cutOffPoint = stringToShorten.Length
    End If

    Return stringToShorten.Substring(0, cutOffPoint) + stringToAppend
  End If
End Function

Answer 3

Dim newString = New String(
                 yourString
                     .ToCharArray()
                     .Take(100)
                     .TakeWhile(Function(c) c <> " "c).ToArray())

善，

丹

Answer 4

这是我的C＃扩展方法

    /// <summary>
    /// Creates a shortend version of a string, with optional follow-on characters.
    /// </summary>
    /// <param name="stringToShorten">The string you wish to shorten.</param>
    /// <param name="newLength">
    /// The new length you want the string to be (nearest whole word).
    /// </param>
    public static string ShortenString(this string stringToShorten, int newLength)
    {
        if (newLength > stringToShorten.Length) return stringToShorten;

        int cutOffPoint = stringToShorten.IndexOf(" ", newLength -1);

        if (cutOffPoint <= 0)
            cutOffPoint = stringToShorten.Length;

        return stringToShorten.Substring(0, cutOffPoint);
    }

Answer 5

好像你可以用这样的东西击中它，这不会把最后一个字分成碎片。其他的解决方案似乎导致了“像......这样的句子”，这些句子没有突破字界，但我可能已经错过了，因为我没有仔细检查。

if (text.Length < 100)
    return text;

var words = text.Split(' ');

var sb = new StringBuilder(128);
foreach (string w in words)
{
    if (sb.Length + w.Length > 100)
    {
        sb.Append("...");
        return sb.ToString();
    }
    sb.Append(w).Append(" ");
}

return sb.ToString();

通过这么多字符修剪字符串，但不要删除最后一个字

5 个答案: