求和求平均问题～～～

我又来问了～～上次的问题得到了圆满的解答～～谢谢～～

可是又遇到问题了～～果然是新手呢～～

那个sum 和 avg～～好像是不能运算 varchar类型的～～

可是因为我和OPC连～～数据类型只能定varchar~~

那么在 vb里面能不能求得总和和平均数啊～～

强制类型转换

cint(变量)，把变量强制转换成整型
CDBL(变量),变量强制转换成浮点型

还有很多呢，自己查下帮助也行

改了还是又问题额～～还是说我VARCHAR的问题～～·

下面是我的代码～～好像有点长～～不过毕业设计急～～所以麻烦大家了～～

Private Sub Form_Load()

LSH_T = CInt(LSH_T)

PSH_T = CInt(PSH_T)

HSH_T = CInt(HSH_T)

SA1_T = CInt(SA1_T)

SA2_T = CInt(SA2_T)

SA1_LQ = CInt(SA1_LQ)

SA1_RQ = CInt(SA1_RQ)

SA2_LQ = CInt(SA2_LQ)

SA2_RQ = CInt(SA2_RQ)

sql = "select * from ls"
Adodc1.RecordSource = sql
Set DataGrid1.DataSource = Adodc1
DataGrid1.Caption = ""
Combo1.AddItem "LSH_T"             '在下拉条中添加10个选项名
Combo1.AddItem "PSH_T"
Combo1.AddItem "HSH_T"
Combo1.AddItem "SA1_T"
Combo1.AddItem "SA2_T"
Combo1.AddItem "SA1_LQ"
Combo1.AddItem "SA1_RQ"
Combo1.AddItem "SA2_LQ"
Combo1.AddItem "SA2_RQ"


Combo2.AddItem "最大值"             '
Combo2.AddItem "最小值"
Combo2.AddItem "平均值"
Combo2.AddItem "总和"



End Sub

Private Sub Command2_Click()


If Combo2.Text = "平均值" Then

  sql = "select avg(LSH_T) as LSH_T,avg(PSH_T) as PSH_T,avg(HSH_T) as HSH_T,avg(SA1_T) as SA1_T,avg(SA2_T) as SA2_T,avg(SA1_LQ) as SA1_LQ,avg(SA1_RQ) as SA1_RQ,avg(SA2_LQ) as SA2_LQ,avg(SA2_RQ) as SA2_RQ from ls"
  Adodc1.RecordSource = sql
  Set DataGrid1.DataSource = Adodc1
  Adodc1.Refresh
  DataGrid1.Caption = "平均值"
End If
If Combo2.Text = "总和" Then

  sql = "select sum(LSH_T) as LSH_T,sum(PSH_T) as PSH_T,sum(HSH_T) as HSH_T,sum(SA1_T) as SA1_T,sum(SA2_T) as SA2_T,sum(SA1_LQ) as SA1_LQ,sum(SA1_RQ) as SA1_RQ,sum(SA2_LQ) as SA2_LQ,sum(SA2_RQ) as SA2_RQ from ls"
  Adodc1.RecordSource = sql
  Set DataGrid1.DataSource = Adodc1
  Adodc1.Refresh
  DataGrid1.Caption = "总和"
End If
End Sub

问题已经解决了～～我在OPC里改了数据类型～～

再加上val