VB.Net检查进程是否存在及关闭进程

Dim i As Integer
Dim proc As Process()
 
'判断excel进程是否存在
If System.Diagnostics.Process.GetProcessesByName("excel").Length > 0 Then
    proc = Process.GetProcessesByName("excel")
    '得到名为excel进程个数，全部关闭
    For i=0 to proc.Length -1
        proc(i).Kill()
    Next
End If
proc = Nothing