Using VBScript to find and replace all multi-line text between curly braces of a node within a JSON file

Question

As part of a Windows logon script (hence the VBScript requirement), I would like to set values in a user\'s Google Chrome preferences (stored in a JSON file in the user prof

Answer 1

You can do the replacement with a regular expression:

prefsFile = "%userprofile%\Local Settings\...\Preferences"
prefsFile = CreateObject("WScript.Shell").ExpandEnvironmentStrings(prefsFile)

newPrefs = "..."

Set fso = CreateObject("Scripting.FileSystemObject")

json = fso.OpenTextFile(prefsFile).ReadAll

Set re = New RegExp
re.Pattern = """download"": {[\s\S]*?},"

json = re.Replace(json, """download"": {" & vbCrLf & newPrefs & vbCrLf & "},")

fso.OpenTextFile(prefsFile, 2).Write(json)

The pattern [\s\S] matches any whitespace or non-whitespace character. You can't use . in this case, because that special character does not match newlines, and you want the expression to span multiple lines. The qualifiers * and ? mean "match any number of characters" and "use the shortest match" respectively. That way the expression matches everything between a pair of curly braces after the "download": keyword.