最后调用TryReadImage
第二种、程序法
在例程(Ctrl+E)——应用范围——一般——搜索“error”有一个dev_set_check的例子如下:
// Local iconic variables
Hobject Image;
// Local control variables
Herror Error;
HTuple WindowHandle, FileName, ReadError;
if (HDevWindowStack::IsOpen())
close_window(HDevWindowStack::Pop());
set_window_attr("background_color","black");
open_window(0,0,512,512,0,"","",&WindowHandle);
HDevWindowStack::Push(WindowHandle);
// Error variable 'Error' activated
set_check("~give_error");
FileName = "wrong_name";
Error = read_image(&Image, FileName);
ReadError = (int)Error;
set_check("give_error");
if (0 != (ReadError!=2))
{
Error = write_string(WindowHandle, "wrong file name: "+FileName);
}
//Now the program will stop with an exception(注意 Error = read_image(&Image, FileName);要在set_check前面才有效。)
Error = read_image(&Image, FileName);
//Please note that some tuple operations have no return value. Then, the described approach leads to a
memory leak. Please use the object-oriented approach instead.
//请注意,某些元组操作没有返回值。然后,所描述的方法导致一个内存泄漏。请用面向对象的方法来代替。
举一个实时显示图像窗口中鼠标所在位置的像素亮度的例子
read_image (Image, 'fabrik')
while (1)
dev_set_check ('~give_error')
try
dev_display (Image)
get_mposition (3600, Row, Column, Button)
*在halcon10.0后当鼠标离开图像窗口后,get_mposition算子出现异常。必须要有异常处理才能运行正常!
get_grayval (Image, Row, Column, Grayval)
set_tposition (3600, 24, 24)
write_string (3600, 'Row='+Row)
set_tposition (3600, 64, 24)
write_string (3600, 'Column =' +Column)
set_tposition (3600, 104, 24)
write_string (3600, 'Grayval =' +Grayval)
catch (Exception)
set_tposition (3600, 24, 24)
write_string (3600, Exception)
endtry
dev_set_check ('give_error')
wait_seconds (0.1)
endwhile
原文出自: 点击打开链接