dev_update_var — 在程序执行期间打开或关闭变量窗口的更新功能。
dev_update_var( : : DisplayMode : )
dev_update_var specifies the behavior of the variable window
during program execution.
If DisplayMode is set to 'on', which is the default,
the contents of the variable window (iconic and control variables)
is updated each time a variable is modified by the program.
If the mode is 'off' the values of the control variables and the icons of the iconic variables are not updated before the execution stops.
For measuring the execution time of a sequence of operators all
update options should be switched off in order to reduce the
influence of the runtime of GUI updates in HDevelop.
For this the operators dev_update_pc, dev_update_time,
dev_update_var, and dev_update_window or the
procedures dev_update_on and dev_update_off
can be used.
This option can also be controlled via the Preferences dialog:
Edit -> Preferences
-> Runtime Settings
-> Update Variables.
此算子不支持代码导出。
DisplayMode (输入控制) string → (string)
Mode for graphic output.
默认值： 'off'
值列表： 'off', 'on'
If the values of the specified parameters are correct,
dev_update_var 返回 2 ( H_MSG_TRUE )。否则，将抛出一个异常并返回错误代码。
dev_update_pc,
dev_update_window,
dev_update_time
基础