vb.net取倍数 vbnet substring

VB.NET编写最小公倍数的代码是什么?Dim m, n, r As Integer
Dim gbs As Integer
Dim h As Integer
Dim k As Integer
Dim p As Integer
m = CInt(Me.TextBox1.Text)
n = CInt(Me.TextBox2.Text)
If mn Then
h = m
m = n
n = h
End If
k = m
p = n
r = m Mod n
Do While (r0)
m = n
n = r
r = m Mod n
Loop
gbs = (p * k) / n
Me.TextBox4.Text = CStr(gbs)
Me.TextBox3.Text = CStr(n)
如何用vb做100以内2,3,5的倍数窗体中创建三个check按钮,分别选中表示2的,3的,5的倍数
一个combo控件用于显示结果
Public m As Integer, n As Integer, k As Integer
Private Sub Check1_Click()
m = Check1.Value
n = Check2.Value
k = Check3.Value
Combo1.Clear
Call js(m, n, k)
End Sub
Private Sub Check2_Click()
m = Check1.Value
n = Check2.Value
k = Check3.Value
Combo1.Clear
Call js(m, n, k)
End Sub
Private Sub Check3_Click()
m = Check1.Value
n = Check2.Value
k = Check3.Value
Combo1.Clear
Call js(m, n, k)
End Sub
Sub js(mm As Integer, nn As Integer, kk As Integer)
Dim i As Integer
If mm = 1 Then
If nn + kk = 0 Then
Combo1.Text = "2的倍数"
For i = 1 To 100
If i Mod 2 = 0 Then Combo1.AddItem Str(i)
Next
ElseIf nn = 1 And kk = 0 Then
Combo1.Text = "2和3共同的倍数"
For i = 1 To 100
If i Mod 2 = 0 And i Mod 3 = 0 Then Combo1.AddItem Str(i)
Next
ElseIf nn = 0 And kk = 1 Then
Combo1.Text = "2和5共同的倍数"
For i = 1 To 100
If i Mod 2 = 0 Or i Mod 5 = 0 Then Combo1.AddItem Str(i)
Next
ElseIf nn = 1 And kk = 1 Then
Combo1.Text = "2,3,5的倍数"
For i = 1 To 100
If i Mod 2 = 0 And i Mod 3 = 0 And i Mod 5 = 0 Then Combo1.AddItem Str(i)
Next
End If
Else
If nn = 1 And kk = 0 Then
Combo1.Text = "3的倍数"
For i = 1 To 100
If i Mod 3 = 0 Then Combo1.AddItem Str(i)
Next
ElseIf nn = 0 And kk = 1 Then
Combo1.Text = "5的倍数"
For i = 1 To 100
If i Mod 5 = 0 Then Combo1.AddItem Str(i)
Next
ElseIf nn = 1 And kk = 1 Then
Combo1.Text = "3和5共同的倍数"
For i = 1 To 100
If i Mod 3 = 0 And i Mod 5 = 0 Then Combo1.AddItem Str(i)
Next
End If
End If
End Sub
关于VB.net取整的问题double是双精度 有效数值位52位 表示成指数的形式 即指数11位 即表示成
所以180.89305用2进制表示是10110100.1110010010011110111011001011111110110001010110110101

180.89305在double中存在的实际数值是
1.01101001110010010011110111011001011111110110001010110110101 *2^7
取小数点后 52位有效值后 等于10进制的180.893049999999998
所及加最后变成了 1808930.99999999998
第一次当然输出近似值1808931
第二次int函数去掉了小数点后的数int就是只取整数的部位的不是四舍五入 所以少了1
vb编程中找出100之内的3的倍数,显示时每行不超过6个?只要让循环控制变量从3起步,每次的步长为3,每次输出一个数,当数满六个的时候就换行 。
请教vb.net Marshal.SizeOf取结构体长度的问题,谢谢o这是因为有字节对齐的问题 。每一个变量的首地址必须是它所占字节长度的倍数 。
比如int32长度是4,那么它的首地址只能取0,4,8,12……
下面的图形象的表示了MSG在内存中的储存情况:
OOXXOOOO
第一个和第二个O表示两个BYTE类型的数据 , 两个X表示空地址,里面什么也没放 。后面四个OOOO便是一个int32类型数据也就是Code 。加起来总共占了8个字节的内存
VB.NET picturebox 内绘图完图形放大缩小移动 鼠标控制。比较笨看了VB的代码不明白 求解 。net 不用api就行

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