VB.net数组引发异常

Question

The following sub is throwing a

"Object reference not set to an instance of an object."

exception.

For Each element As Song In modFiles.getSongs()
    Dim col(2) As String
    Dim item As ListViewItem
    col(0) = element.SongTitle
    col(1) = element.PlayTime
    col(2) = element.SongFilename
    item = New ListViewItem(col)
    setList.Items.Add(item)
Next

The exception is thrown on lines

col(0) = element.SongTitle
col(1) = element.PlayTime
col(2) = element.SongFilename

Any help would be appreciated

Answer 1

Your array declaration is fine.

Your For Each iterator is returning a null object somewhere. Wrap a null test around the body of the loop.

For Each element As Song In modFiles.getSongs()
    If element IsNot Nothing Then
        Dim col(2) As String
        Dim item As ListViewItem
        col(0) = element.SongTitle
        col(1) = element.PlayTime
        col(2) = element.SongFilename
        item = New ListViewItem(col)
        setList.Items.Add(item)
    End If
Next

Answer 2

您忘记了数组中的一个元素

Dim col(3) As String