SVG_Read_last_error -> Function result
| Parameter | Type | Description | |
|---|---|---|---|
| Function result | Longint | ← | Number of last error |
The SVG_Read_last_error command returns the number of the last error that occurred during the execution of a 4D SVG component command and resets this error.
The error number returned can be specific to a component command or may be an error generated by 4D. The following errors are generated by the component:
| 8850 | Insufficient number of parameters |
|---|---|
| 8851 | Invalid parameter type |
| 8852 | Invalid reference |
| 8853 | Incorrect value for attribute |
| 8854 | The element does not accept this command |
| 8855 | Invalid (ID not found in document) object name (symbol, marker, filter, etc.) |
| 8856 | DTD file not found |
| 8857 | Incorrect value for a parameter |
| 8858 | Unknown error |
Given the “SVG_error_mgmt” method of the example for the SVG_Set_error_handler command:
//Installation of error-handling method
$ Error_Method_Txt:=SVG_Set_error_handler("SVG_error_mgmt")
//from now on it is the SVG_error_mgmt method that will be executed in the case of an error
//Creation of new SVG document
$SVG:=SVG_New(1200;900;"SVG Component Test";"";True)
SVG_SET_VIEWBOX($SVG;0;0;1500;1000)
If(SVG_Read_last_error=0)
...
Else
//The SVG_error_mgmt method has been called and has received the error number
End if
//Uninstalling of error-handling method
SVG_Set_error_handler
Given the following SVG_error_mgmt method:
var $1 : Integer
var $2 : Text
//Keep the error and the context
errorNumber:=$1
commandName:=$2
//Set the OK system variable to 0
OK:=0
This method can be used as follows:
// Installation of error-handling method
$ Error_Method_Txt:=SVG_Set_error_handler("SVG_error_mgmt")
// Creation of new SVG document
$SVG:=SVG_New(1200;900;" SVG Component Test ";"";True)
SVG_SET_VIEWBOX($SVG;0;0;1500;1000)
If(OK=1)
...
Else
ALERT("Error No."+String(errorNumber)+" during execution of the command \""+commandName+"\"")
End if
// Uninstalling of error-handling method
SVG_Set_error_handler