The function ReadEmpNo (Port, BaudRate: Integer; EmpNo: an array of byte) : Integer; Stdcall; External 'Reader. DLL'; 

Type 
TMyThread=class (TThread) 
Protected 
Procedure the Execute; Override. 
end; 

Procedure TMyThread. Execute; 
Var 
I: Integer; 
EmpNo: array [0.. 10] of byte; 
StrNo: string; 
The begin 
FreeOnTerminate:=True; {this allows threads execute immediately after the release} 
Try 
//while (true) do 
The begin 
StrNo:='; 
If ReadEmpNo (StrToInt (' 1 ') - 1, 19200, EmpNo)=0 then 
The begin 
//ShowMessage (Trim (PChar (@ EmpNo))); 
StrNo:=Trim (PChar (@ EmpNo)); 

end; 
 FormC_input. Edt_no. Text:='22222';//strNo;  

Sleep (3000); 
end; 

The finally 
//variable. Free; 
end; 
end; 

Problem is in the red part, it is this FORM of unable to get value up. The control.

But the code I wrote another with D7. A program can be out.

CodePudding user response:

Is the line 26

Color can't

 
FormC_input. Edt_no. Text:='22222';//strNo; 

CodePudding user response:

Threads do not modify the VCL, directly Delphi VCL is not secure multithreaded,
Add a procedure to Form, and then using the Synchronize threads synchronization to the main thread of execution, in this procedure, modify the value of the VCL

CodePudding user response:

Agree with upstairs, as long as to allow access to the UI, you need to use synchronization function