VBA：从文本文件中读取特定的字符串，然后如果未找到则打开msgbox

Question

晚上好

今天，我一直在尝试找出如何在VBA中打开文本文件，并查找特定的字符串。我需要这样做，以便如果字符串：

'productactivated = true'

它确定是否在用户窗体上显示一条消息，告知用户激活。

几天前，我寻求帮助来打开文本文件并进行一些读写操作，所以我想到了这个

Open "application.txt" For Output As #1
ClngLine = lngLine + 1
    Line Input #f, strLine
    If InStr(1, strLine, strSearch, vbBinaryCompare) > 0 Then
        MsgBox "Search string found in line " & lngLine, vbInformation
        blnFound = True
Close #1

如果有人知道如何解决此问题，我将不胜感激

欢呼

Answer 1

对于您的解决方案，将使用两个文件来显示如何读取和写入文本文件。添加该文字只是为了向您展示如何做到这一点，但根据您的问题陈述，解决方案似乎并不需要它。为此，所有文件都位于同一文件夹中。

第一个文件是正在读取的文件。出于演示目的，由于未提供数据，因此使用以下数据创建了该数据，并将其命名为“ TextFile.txt ”：

This is the first line.
This is the second line and has productactivated=true.
Third line lays here.
productactivated=true is found in line four.

第二个文件是要写入的文件。出于演示目的，只是为了演示它是如何完成的，但不需要您提出任何问题，并将其命名为“ TextFile.txt ”：

This is the first line.
This is the second line and has productactivated=true.
Third line lays here.
productactivated=true is found in line four.

VBA代码：

Sub search_file()
    Const ForReading = 1, ForWriting = 2
    Dim FSO, FileIn, FileOut, strSearch, strTmp

    'FileSystemObject also called as FSO, provides an easy object based model to access computer’s file system.
    Set FSO = CreateObject("Scripting.FileSystemObject")
    'Set FileIn to the file for reading the text into the program.
    Set FileIn = FSO.OpenTextFile("TextFile.txt", ForReading)
    'Set FileOut to the file for writing the text out from the program.
        'This was added just to show "how to" write to a file.
    Set FileOut = FSO.OpenTextFile("TextFileRecordsFound.txt", ForWriting, True)
    'Set the variable to the string of text you are looking for in the file you are reading into the program.
    strSearch = "productactivated=true"

    'Do this code until you reach the end of the file.
    Do Until FileIn.AtEndOfStream
        'Store the current line of text to search to work with into the variable.
        strTmp = FileIn.ReadLine
        'Determines whether to display a message
        '(Find out if the search text is in the line of text read in from the file.)
        If InStr(1, strTmp, strSearch, vbTextCompare) > 0 Then
            'Display a message telling the user to activate.
            MsgBox strSearch & "was found in the line:" & vbNewLine & vbNewLine & strTmp, , "Activate"
            'Write the line of text to an external file, just to demo how to.
            FileOut.WriteLine strTmp
        End If
    Loop 'Repeat code inside Do Loop.

    'Close files.
    FileIn.Close
    FileOut.Close
End Sub