Private Sub Command1_Click()
Open "out.txt" For Output As #1
temp = isprime()
Print #1, temp
Text1.Text = temp
Close #1
End Sub

Private Sub Form_Load()
Text1.Text = ""
Command1.Caption = "计算"
End Sub
Public Function isprime() As Double
Dim i As Integer, j As Integer, temp As Long
For i = 100 To 200
For j = 1 To Int(Sqr(i))
If i Mod j = 0 Then
Exit For
Else
temp = temp + i
End If
Next
Next
End Function

哪点错了

你的Function是没有传回值吧.
究竟是什么错误呢?.
下次没有说什么错误,光发个代码出来的.一率删贴

如何传回值？错在不能运行程序，单击command1 text1的显示 是0

Public Function isprime() As Double
Dim i As Integer, j As Integer, temp As Long
For i = 100 To 200
For j = 1 To Int(Sqr(i))
If i Mod j = 0 Then
Exit For
Else
temp = temp + i
End If
Next
Next
isprime=temp
End Function

j=1,第一个i mod j=0,j=1时循环就结束了

Private Sub Command1_Click()
Dim blnPrime As Boolean
For i = 100 To 200
blnPrime = True
For j = 2 To Sqr(i)
If i Mod j = 0 Then
blnPrime = False
Exit For
End If
Next j
If blnPrime Then Debug.Print i,
Next i
End Sub

你的函数错在没有返回值，还有100到200的循环应该放在调用isprime的函数里

下面是编辑时加上去的！无奈了……

Private Function isPrime(iNum As Integer) As Boolean
For j = 2 To Sqr(iNum)
If iNum Mod j = 0 Then
isPrime = False
Exit Function
End If
Next j
isPrime = True
End Function

Private Sub Command1_Click()
Dim i As Integer
Open "out.txt" For Output As #1
For i = 100 To 200
If isPrime(i) = True Then
Print #1, i
End If
Next i
End Sub

[此贴子已经被作者于2007-3-16 13:32:44编辑过]

Open "out.txt" For Append As #1