WINCC写数据库
在WINCC的图形编辑器中,在输入域的属性中。选择事件。再选择键盘的释放动作,在动作代码框中写下例如以下代码:
Dim conn,rs
Dim strsql
Dim a
a=HMIRuntime.Tags("datavariable").Read
Set conn=CreateObject("adodb.connection")
Set rs=CreateObject("adodb.recordset")
conn.Provider = "sqloledb"
conn.open "SERVER=Yang-PC\WINCC;uid=sa;pwd=sa;database=datasavetest"
strsql="insert into tt_ch(TagValue)VALUES('" & a &"')"
Set rs=conn.execute(strsql)
conn.close
Set rs=Nothing
Set conn=Nothing
End If
如此,就可以实现WINCC的实时数据向SQL SERVER的数据写入。
WINCC读数据库
Dim conn,rs
Dim strsql
Dim temp1,temp2
Set conn=CreateObject("adodb.connection")
Set rs=CreateObject("adodb.recordset")
conn.Provider = "sqloledb"
conn.open "SERVER=YANG-PC\WINCC;uid=sa;pwd=1988525;database=datasavetest"
strsql="select * from table_1"
Set rs=conn.execute(strsql)
rs.movenext'读取数据集中的下一条还能够通过数据集的其它属性进行操作
temp1 = rs.Fields(0).Value '取第一列的值
'temp1 = rs("text")从数据集中取字段“text”的值
Set temp2 = HMIRuntime.Tags("textdataAuto")
temp2.Read
temp2.Write temp1
conn.close
Set rs = Nothing
Set conn=Nothing
假设我们须要连接的是access数据库,仅仅须要将
"SERVER=YANG-PC\WINCC;uid=sa;pwd=1988525;database=datasavetest"
替换为
"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=datasavetest"
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