Question

我想做一个申请。

在这个appplication中，我希望得到我选择的2个字符之间的字符串。

例如：“Hello world”。

如果我选择了字符“e”和“d”，这将得到“llo worl”

我正在尝试帮助Microsoft文档中的Substring方法。但我找不到如何设置字符串的最后一个限制。

感谢您的帮助

Answer 1

Dim MainString As String 'the main string 
Dim FirstChar As String 'first character
Dim lastchar As String 'second char
Dim finalastring As String 'final string after the work is done

Dim FirstCharIndex As Integer 'the index where first char is located
Dim LastCharIndex As Integer 'the index where last char is located

Private Sub Button1_Click(sender As System.Object, e As System.EventArgs) Handles Button1.Click
    MainString = TextBox1.Text 'Hello World
    FirstChar = TextBox2.Text 'e
    lastchar = TextBox3.Text 'd

    FirstCharIndex = MainString.IndexOf(FirstChar) 'this will return 1 in this condition
    LastCharIndex = MainString.LastIndexOf(lastchar) 'this will return 10

    'now, Final String

    finalastring = MainString.Substring(FirstCharIndex, (LastCharIndex - FirstCharIndex))

    TextBox4.Text = finalastring



End Sub

Answer 2

您仍然可以使用Substring来实现这一目标：

    Public Sub Main()
        Dim test as String = "Hello World"
        Console.WriteLine(StringBetweenChars(test,"e","d"))

    End Sub

    Public Function StringBetweenChars(ByVal fullText, ByVal start, ByVal ending) as String
        Dim x,j as integer
        x = fullText.IndexOf(start) + 1
        j = fullText.IndexOf(ending) 
        If(j <> -1) Then
            return fullText.Substring(x, j-x)           
            Else
            return fullText.Substring(x, fullText.Length - x)
        End If
    End function

打印出来：llo Worl

获取2个特定字符之间的字符串

2 个答案: