文本框验证的方法 [英] Method for textbox validation

问题描述

我有一个Windows窗体应用程序，该应用程序有一个文本框，供用户输入有关其工作的特殊注释.我们遇到了麻烦，因为用户一直在使用Microsoft Word键入这些注释，然后他们将它们复制/粘贴到我的应用程序中.这是一个问题，因为例如，如果在Word中键入...，它将转换为椭圆字符.另外，如果您键入-它可以将其转换为连字符.这些可以很好地粘贴到文本框中，但是最终这些数据将被保存到不喜欢这些字符的iSeries中.因此，我整理了一些代码，它们既可以作为用户类型使用，也可以作为用户使用复制/粘贴功能将代码替换为对应的麻烦字符，并使用星号替换所有未知字符的代码.它有效，但是我感觉必须有一种更好，更有效的方法来做到这一点.有人有什么建议吗?

I have a windows forms application that has a textbox for users to enter special comments about their work. We''ve been having trouble because users have been using Microsoft Word to type these comments and then they copy/paste them into my application. It''s a problem because, for example, in Word if you type ... it converts it to an elipse character. Also if you type - it can convert it into a hyphen character. These are fine to paste into the textbox, but eventually this data is getting saved to an iSeries which doesn''t like these characters. So I put together some code which should work both as the user types and if they use copy/paste to replace known trouble characters with counterparts and any unkown characters with an asterisk. It works, but I have a feeling there must be a better and more efficient way to do it. Does anyone have any suggestions?

Private Sub txtSpecialReport_TextChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles txtSpecialReport.TextChanged
        'Only allow known characters to be pasted or typed into txtSpecialReport to avoid errors on iSeries
        '\w is for a-zA-Z0-9, \s is for spaces, tabs, returns, the rest are allowed special characters
        Dim myRegex As New System.Text.RegularExpressions.Regex("[\w\s\!\@\#\$\%\^\&\*\(\)\-\=\+\[\]\{\}\\\|\;\:\'\,\<\.\>\/\?\""]")
        Dim sb As New System.Text.StringBuilder
        Dim intStart As Integer = txtSpecialReport.SelectionStart
        For Each myChar As Char In txtSpecialReport.Text.ToCharArray
            If Not myRegex.IsMatch(myChar) Then
                'known replacements
                Select Case Asc(myChar)
                    Case 63
                        'Replace an ascii 63 with ascii 39
                        myChar = "'"
                    Case 133
                        'Replace an ascii 133 elipses with a period
                        'don't want to change the length of the string, so don't replace with three periods
                        myChar = "."
                    Case 146
                        'Replace an ascii 146 with ascii 39
                        myChar = "'"
                    Case 150
                        'Replace an ascii 150 dash with an ascii 45 dash
                        myChar = "-"
                    Case Else
                        'Any other characters replace with an asterisk
                        myChar = "*"
                End Select
            End If
            sb.Append(myChar)
        Next
        txtSpecialReport.Text = sb.ToString
        txtSpecialReport.SelectionStart = intStart
    End Sub

推荐答案

\％\ ^ \& \ * \(\)\-\ == ++ [\] \ {\} \\\ | \; \:\'\，\< \.\> \//\?\"]") Dim sb As New System.Text. StringBuilder Dim intStart As 整数 = txtSpecialReport.SelectionStart 对于 每个 myChar As 字符 在中txtSpecialReport.Text.ToCharArray 如果 不是 myRegex.IsMatch(myChar)然后 ' 已知替代品 选择 案例 Asc(myChar) 案例 63 ' 用ascii 39替换ascii 63 myChar = " 案例 133 ' 用时间段替换ASCII 133椭圆 ' 不想更改字符串的长度，因此请勿替换为三个句点 myChar = " 案例 146 ' 将ascii 146替换为ascii 39 myChar = " 案例 150 ' 用ascii 45破折号代替ascii 150破折号 myChar = " 案例 其他 ' 其他任何字符都替换为星号 myChar = " 结束 选择 结束 如果 sb.Append(myChar) 下一步 txtSpecialReport.Text = sb.ToString txtSpecialReport.SelectionStart = intStart 结束 子

\%\^\&\*\(\)\-\=\+\[\]\{\}\\\|\;\:\'\,\<\.\>\/\?\""]") Dim sb As New System.Text.StringBuilder Dim intStart As Integer = txtSpecialReport.SelectionStart For Each myChar As Char In txtSpecialReport.Text.ToCharArray If Not myRegex.IsMatch(myChar) Then 'known replacements Select Case Asc(myChar) Case 63 'Replace an ascii 63 with ascii 39 myChar = "'" Case 133 'Replace an ascii 133 elipses with a period 'don't want to change the length of the string, so don't replace with three periods myChar = "." Case 146 'Replace an ascii 146 with ascii 39 myChar = "'" Case 150 'Replace an ascii 150 dash with an ascii 45 dash myChar = "-" Case Else 'Any other characters replace with an asterisk myChar = "*" End Select End If sb.Append(myChar) Next txtSpecialReport.Text = sb.ToString txtSpecialReport.SelectionStart = intStart End Sub

不幸的是，AFAIK有top绝对不能用正则表达式将其中一个"替换为其中一个".
您可以使用MatchEvaluator消除对String构建器的需要，从而对其进行一些整理.使正则表达式只是已知无效字符的列表，并且:

Unfortunately, AFAIK there is no way top make a regex which replaces "one of these" with "one of those".
You can clean it up a bit, by using a MatchEvaluator to remove the need for a String builder. Make the regex just a list of known invalid characters and:

result = myRegex.Replace(input, New MatchEvaluator(AddressOf ReplaceSpecials))

Private Function ReplaceSpecials(match As Match) As String
	Select Case Asc(match.Value(0))
		Case 63
			Return "''"
		Case 133
			Return "."
	End Select
	Return "*"
End Function

未经测试，但您有一个大致的概念:请参阅 MSDN [ ^ ]了解更多详细信息.


-KSCHULER 添加了缺少"AddressOf"关键字以更正语法，并删除了该关键字；

This isn''t tested, but you get the general idea: See MSDN[^] for better details.


-- KSCHULER Added the "AddressOf" keyword that was missing to correct syntax and removed ;

这篇关于文本框验证的方法的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！