网站建设作用/网络营销的特点有几个

相比一些常用的字符串操作函数，正则表达式才是王者啊，功能强大很多！

'一 正则表达式'正则表达式是处理字符串的外部工具，它可以根据设置的字符串对比规则，进行字符串的对比、替换等操作。'正则表达式的作用：'1、完成复杂的字符串判断'2、在字符串判断时，可以最大限度的避开循环，从而达到提高运行效率的目的。'二 使用方法'1、引用法'点击VBE编辑器菜单：工具 - 引用，选取: Microsoft VBScript Regular Expressions 5.5,引用后在程序开始进行如下声明'Dim regex As New RegExpSub t1()Dim reg As New RegExpEnd Sub'2、直接他建法
'     代码引用 (后期绑定)
'     Dim regex As Object
'     Set regex = CreateObject("VBScript.RegExp") '创建正则对象Sub t2()Dim reg As ObjectSet reg = CreateObject("VBScript.RegExp")End Sub'三 常用属性'1 Global属性:'如果值为true,则搜索全部字符'如果值为False,则搜索到第1个即停止'1 例:Sub t3()Dim reg As New RegExpDim srsr = "ABCEA"With reg.Global = True.Pattern = "A"Debug.Print .Replace(sr, "")End WithEnd Sub'2 IgnoreCase 属性'如果搜索是区分大小写的，为False（缺省值）True不分'3 Pattern 属性' 一个字符串，用来定义正则表达式。缺省值为空文本。'4 Multiline 属性,字符串是不是使用了多行,如果是多行,$适用于每一行的最后一个Sub t4()Dim reg As New RegExpDim srsr = "AEA" & Chr(10) & "ABCA"With reg.Global = True.MultiLine = True'.Pattern = "A$".Pattern = "^A"Debug.Print .Replace(sr, "")End WithEnd Sub'5  Execute 方法'返回一个 MatchCollection 对象，该对象包含每个成功匹配的 Match 对象,'返回的信息包括:'FirstIndex:开始位置'Length; 长度'Value:长度Sub t5()Dim reg As New RegExpDim sr, matcsr = "A454BCEA5"With reg.Global = True.Pattern = "A\d+"Set matc = .Execute(sr)End WithStopEnd SubFunction ns(rg)Dim reg As New RegExpDim sr, ma, s, m, xWith reg.Global = True.Pattern = "\d*\.?\d*"Set ma = .Execute(rg)For Each m In mas = s + Val(m)Next mEnd Withns = s' StopEnd Function'6、Text方法'返回一个布尔值，该值指示正则表达式是否与字符串成功匹配。其实就是判断两个字符串是否匹配成功Sub t7()Dim reg As New RegExpDim srsr = "BCR6EA"With reg.Global = True.Pattern = "\d+"If .test(sr) Then MsgBox "字符串中含有数字"End WithEnd SubFunction 提取中文(rg As String, k As Integer)Dim regx As New RegExpWith regx.Global = TrueIf k = 1 Then.Pattern = "\D"ElseIf k = 2 Then.Pattern = "\w"End If提取中文 = .Replace(rg, "")End WithEnd Function