ReadVals

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Manual > Server Creation Guide > Interface > IPLink-Interface > IPLinkClient Library > IPLinkClient Library Reference > Method >

ReadVals

 

Reads multiple tag values in bulk.

 

syntax

AxIPLink1.ReadVals(

         Count,

         TagPaths,

         &Values,

         &Results,

         DataSource

         )

 

Parameters

 

Count

 

Type:

Numeric

 

Specifies the number of tags to read.

 

TagPaths

 

Type:

String()

 

Specify the tag path as an array. (Array tags cannot be specified.)

 

&Values

 

Type:

Object

 

The read values are returned as an array. This is only valid when the return value is True.

 

&Results

 

Type:

Object

 

The quality of each tag is returned as a Boolean. It is only valid when the return value is True.

 

DataSource

 

Type:

Numeric

 

0 – client cache value. 1 – server cache value. 2 – device value.

 

Return Value

 

 

Type:

Boolean

 

FALSE - Failure. TRUE - Success.

 

ReadVals reads the values of multiple tags at once.

Therefore, if you want to read the values of multiple tags,ReadValThis is faster than calling the method multiple times.

Before reading values with the ReadVals method,AddTagThe tag must be registered using the method.

If the call to ReadVals is successful, the return value is set to True. Only when this value is True will Values/Results be valid.

Values stores the acquired tag values, Results stores the quality of the values for each tag (whether communication was successful or not), and when Results(x) is True, Values(x) stores a valid value.

For more information about DataSourceReadValSee Methods.

 

 

 

 

Dim TagPaths(2) As String
Dim Values As Object = Noting
Dim Results As Object = Noting
TagPaths(0) = "U01.F01.T01"
TagPaths(1) = "U01.F01.T02"
If AxIPLink1.ReadVals(2, TagPaths, Values, Results, 1) Then
    For i = 0 To 1
        If Results(i) Then
            txtValue(i).Text = Values(i)
        Else
            txtValue(i).Text = "Error!"
        End If
    Next i
Else
    For i = 0 To 1
        txtValue(i).Text = "Error!"
    Next i
End If

 

reference

 

AddTag

ReadVal