# ScriptReadAppSignal Method - neoVI API

This method is used to read an application signal from a script running on a neoVI device.

{% tabs %}
{% tab title="C/C++ Declare" %}

```cpp
int _stdcall icsneoScriptReadAppSignal(void * hObject, unsigned int iIndex, double *dValue);
```

{% endtab %}

{% tab title="Visual Basic .NET Declare" %}

```vbnet
Public Declare Function icsneoScriptReadAppSignal Lib “icsneo40.dll” (ByVal hObject As IntPtr, ByVal iIndex As UInt32, ByRef dValue As Double) As Int32
```

{% endtab %}

{% tab title="C# Declare" %}

```csharp
[DllImport(“icsneo40.dll”)] public static extern Int32 icsneoScriptReadAppSignal(IntPtr hObject, UInt32 iIndex, ref double dValue);
```

{% endtab %}
{% endtabs %}

**Parameters**

hObject

\[in] Specifies the driver object created by [OpenNeoDevice](/neovi-api/win32-api-overview-intrepidcs-api/basic-functions-overview-intrepidcs-api/openneodevice-method-intrepidcs-api.md).

unsigned int iIndex

\[in] The index value of the transmit message to read

double \*dValue

\[in] Contains the current value of the application signal.

**Return Values**

1 if the function succeeded. 0 if it failed for any reason. [GetLastAPIError](/neovi-api/win32-api-overview-intrepidcs-api/error-functions-overview-intrepidcs-api/getlastapierror-method-intrepidcs-api.md) must be called to obtain the specific error. The errors that can be generated by this function are:

NEOVI\_ERROR\_DLL\_NEOVI\_NO\_RESPONSE = 75

NEOVI\_ERROR\_DLL\_SCRIPT\_INVALID\_APPSIG\_INDEX = 225

NEOVI\_ERROR\_DLL\_SCRIPT\_NO\_SCRIPT\_RUNNING = 226

**Remarks**

The script containing the specified application signal must have been successfully downloaded to the neoVI using [ScriptLoadScript](/neovi-api/win32-api-overview-intrepidcs-api/deprecated-functions-overview-intrepidcs-api/coremini-script-interface-overview-intrepidcs-api/scriptload-method-intrepidcs-api.md). The script must also have been started using [ScriptStart](/neovi-api/win32-api-overview-intrepidcs-api/deprecated-functions-overview-intrepidcs-api/coremini-script-interface-overview-intrepidcs-api/scriptstart-method-intrepidcs-api.md). This function will fail if [ScriptStop](/neovi-api/win32-api-overview-intrepidcs-api/deprecated-functions-overview-intrepidcs-api/coremini-script-interface-overview-intrepidcs-api/scriptstop-method-intrepidcs-api.md) has been called. The valid index values for application signals within a script can be found in the <mark style="color:orange;">cmvspy.vs3cmb.h</mark> file that is produced by Vehicle Spy. Please see Vehicle Spy documentation.

### Examples

{% tabs %}
{% tab title="C/C++ Example:" %}

```cpp
int iRetVal;
unsigned long lLastErrNum;
double dValue = 0;

iRetVal = icsneoScriptReadAppSignal(hObject, App_Signal_1, &dValue);
if(iRetVal == 0)
{
    printf("\nFailed to read the application signal.);
}
else
{
    printf("\nApplication signal = %f\r\n", dValue);
}
```

{% endtab %}

{% tab title="C# Example:" %}

```csharp
Int32 iResult;
Double ValueToSet=0;

//Read App signal
iResult = icsNeoDll.icsneoScriptReadAppSignal(m_hObject, Convert.ToUInt32(cboAppSig.SelectedIndex),ref ValueToSet);

if (iResult == 0)
{
    txtAppSigVal.Text = "Problem!";
}
else
{
    txtAppSigVal.Text = Convert.ToString(ValueToSet);
}
```

{% endtab %}

{% tab title="Visual Basic .NET Example:" %}

```vbnet
Dim iResult As Int32
Dim ValueToSet As Double

'//Read App signal
iResult = icsneoScriptReadAppSignal(m_hObject, Convert.ToUInt32(cboAppSig.SelectedIndex), ValueToSet)

If iResult = 0 Then
    txtAppSigVal.Text = "Problem!"
Else
    txtAppSigVal.Text = Convert.ToString(ValueToSet)
End If
```

{% endtab %}
{% endtabs %}


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