VB中 k = Picture1.Point(x, y)为什么会等于-1?

VB中 k = Picture1.Point(x, y)为什么会等于-1? 我只会用vb绘制一次函数图象怎么样画二次的代码类似于Private Sub Cmd1_Click()k = Val(InputBox(k))b = Val(InputBox(b))Picture1.ClsPicture1.ScaleMode = 3Picture1.Scale (-150, 150)-(150, -150)Picture1.DrawWidth = 1Picture1.Line 怎么样用vb绘制二次函数图象,我只会画一次的代码类似于Private Sub Cmd1_Click()k = Val(InputBox(k))b = Val(InputBox(b))Picture1.ClsPicture1.ScaleMode = 3Picture1.Scale (-150,150)-(150,-150)Picture1.DrawWidth = 1Picture1.Line ( vb这句话是什么意思?Picture2.PaintPicture Picture1.Picture, J * Picture1.ScaleWidth, Picture1.ScaleHeight vb中Picture1.Print i - 1; Tab(10);这句什么意思?print后写的什么意思? VB中在picturebox中应用Line函数为什么画不出直线form1.Picture1.Line (300,300)-(9000,300),QBColor(1)对,我放在了form_Load里面了. VB中move函数的问题Picture1.Move 0,0,ScaleWidth - VScroll1.Width,ScaleHeight - HScroll1.Height后面的ScaleWidth - VScroll1.Width,ScaleHeight - HScroll1.Height表示什么意思? VB已经绘制一条直线,怎么使这条直线绕原点旋转一定角度在VB中,我画出了如下直线：For xian = -100 To 100 Step 25Picture1.Line (-Sqr(10000 - xian * xian),xian)-(Sqr(10000 - xian * xian),xian),vbBlacknext现在我想这条 VB中Chr(k)的意思Vb中常用到 用VB子过程,算sin(x),为啥总是不对啊啊T TPrivate Sub Command1_Click()Picture1.ClsDim n As Integer, x As Singlen = Val(Text1.Text)x = Val(Text2.Text)Picture1.Print mysin(n, x)End SubPrivate Function mysin(ByVal n%, ByVal x!) As DoubleDim d vb 中2=3 VB中a>=band VB中X = RT VB中 sum.Value = sum（k,n）=1^k+2^k+...+n^k 的vb编码 sum（k,n）=1^k+2^k+...+n^k 的vb编码 VB中, vb中