I get the error "startIndex cannot be larger than length of string. Parameter name: startIndex" when I run the following code. The error occurs on this line and I think it is to do with the line.substring. The code runs smoothly when I take out line.Substring(11, 2) = "24" and run the code as If line.StartsWith("123") Then currentRecord.ID = line.

I can't seem to get rid of the error.

Dim lines = File.ReadLines(filePath)
If (line.StartsWith("123") And line.Substring(11, 2) = "24") Then currentRecord.ID = line

CodePudding user response：

You need to check the line is long enough to access the substring at that position and length. AndAlso conditions will only trigger if the previous condition = true. If your version of VB.NET doesn't support AndAlso you will need to use nested ifs.

Dim lines = File.ReadLines(filePath)
If (line.StartsWith("123") AndAlso Len(line)>=14 AndAlso line.Substring(11, 2) = "24") Then currentRecord.ID = line