对contains(),中变量，不能识别，求助了

\'\'\'对输入标准进行标准化，体系+推荐+标准号+年号（如果有，在考虑中）
\'\'\'
Dim str As String = args(0)
Dim std() As String = {"GB","HG","SH","JB","ASME","ASTM","DIN"} \'\'\'标准体系数组
Dim std_spec() As String = {"","","",""}

For Each std_tp As String In std
    MessageBox.Show(std_tp)
    If str.Contains( std_tp ) Then   \'\'\'if str.contains("" & std_tp & "") then（也尝试了）
        std_spec(0) = std_tp
        str.Replace(""& std_tp &"","")
    Else
        std_spec(0) = "未匹配"
    End If
Next

Return std_spec(0) 

经高手指点，找到问题

1、是逻辑上出问题了，匹配到后，应该退出循环，添加exit for

2、contains 可以直接使用变量名

是不是大小写的问题？

If str.ToLower.Contains( std_tp.ToLower ) Then

测试过了，都是同一状态

改一下

Dim str As String = ”123HG789"
Dim std() As String = {"GB","HG","SH","JB","ASME","ASTM","DIN"} \'\'\'标准体系数组
Dim std_spec() As String = {"","","",""}

For Each std_tp As String In std
    If str.Contains( std_tp ) Then
        std_spec(0) = std_tp
        str = str.Replace(std_tp,"")
        exit for
    Else
        std_spec(0) = "未匹配"
    End If
Next

msgbox(std_spec(0) & vbcrlf & str)