各位好:   請問function type的使用方法.      Type     TBooleanMethod = function():Boolean of object;     TTestMethod = function():string of object;     procedure showtest (testMethod1:TBooleanMethod;testMethod2:TTestMethod);      以上的宣告我會用, 可是碰到需要帶值運算的不會耶..< > 想請問該怎麼做呢?? < > compile後會一直出現型態不符的現象.. T1BooleanMethod = function(const time_str : string):Boolean of object; TTestMethod = function():string of object; procedure showtest (testMethod1:TBooleanMethod;testMethod2:TTestMethod); 麻煩各位了..

Typing error?    T1BooleanMethod = function(const time_str : string):Boolean of object; TTestMethod = function():string of object; procedure showtest (testMethod1:T1BooleanMethod;testMethod2:TTestMethod); What is the definition for testMethod1 and testMethod2?

不好意思喔, 我再描述清楚一點.. 類型一, 我會用 type TBooleanMethod = function():Boolean of object; TTestMethod = function():string of object; function test2:string; function test3:Boolean; procedure showtest(TestMethod1:TBooleanMethod;TestMethod2:TTestMethod); procedure showtest(TestMethod1: TBooleanMethod; TestMethod2: TTestMethod); begin if Testmethod1=true then showmessage('true' Testmethod2) else showmessage('false' Testmethod2) end; // 實作時 showtest(test3,test2); 類型二, 其中的T1BooleanMethod, Compile 時會出現型態不符, 我不知道要怎麼寫... T1BooleanMethod = function(const time_str : string):Boolean of object; T1TestMethod = function:string of object; function bTest(date : string ): Boolean; function sTest:string; procedure show(TestMethod1:T1BooleanMethod;TestMethod2:T1TestMethod); procedure showtest(TestMethod1: TBooleanMethod; TestMethod2: TTestMethod); begin try TestMethod1;//這裡會出現型態不符 TestMethod2; finally MsgBox('error!'); end; end; // 實作時 showtest(btest,stest) 請再幫我看看, 謝謝.~

不好意思喔, 我再描述清楚一點.. 類型一, 我會用 type TBooleanMethod = function():Boolean of object; TTestMethod = function():string of object; function test2:string; function test3:Boolean; procedure showtest(TestMethod1:TBooleanMethod;TestMethod2:TTestMethod); procedure showtest(TestMethod1: TBooleanMethod; TestMethod2: TTestMethod); begin if Testmethod1=true then showmessage('true' Testmethod2) else showmessage('false' Testmethod2) end; // 實作時 showtest(test3,test2); 類型二, 其中的T1BooleanMethod, Compile 時會出現型態不符, 我不知道要怎麼寫... T1BooleanMethod = function(const time_str : string):Boolean of object; T1TestMethod = function:string of object; function bTest(date : string ): Boolean; function sTest:string; procedure show(TestMethod1:T1BooleanMethod;TestMethod2:T1TestMethod); procedure showtest(TestMethod1: TBooleanMethod; TestMethod2: TTestMethod); begin try TestMethod1;//這裡會出現型態不符 TestMethod2; finally MsgBox('error!'); end; end; // 實作時 showtest(btest,stest) 請再幫我看看, 謝謝.~

You need to specify the arguments...    

引言: 不好意思喔, 我再描述清楚一點.. 類型一, 我會用 type TBooleanMethod = function():Boolean of object; TTestMethod = function():string of object; function test2:string; function test3:Boolean; procedure showtest(TestMethod1:TBooleanMethod;TestMethod2:TTestMethod); procedure showtest(TestMethod1: TBooleanMethod; TestMethod2: TTestMethod); begin if Testmethod1=true then showmessage('true' Testmethod2) else showmessage('false' Testmethod2) end; // 實作時 showtest(test3,test2); 類型二, 其中的T1BooleanMethod, Compile 時會出現型態不符, 我不知道要怎麼寫... T1BooleanMethod = function(const time_str : string):Boolean of object; T1TestMethod = function:string of object; function bTest(date : string ): Boolean; function sTest:string; procedure show(TestMethod1:T1BooleanMethod;TestMethod2:T1TestMethod); procedure showtest(TestMethod1: TBooleanMethod; TestMethod2: TTestMethod); begin try TestMethod1('your time_str here');//這裡會出現型態不符 TestMethod2; finally MsgBox('error!'); end; end; // 實作時 showtest(btest,stest) 請再幫我看看, 謝謝.~

Hi william: Thanks your reply, but I still have some question.. procedure TMyDateTime.ConfirmTime(SetTimeMethod: TSetTimeMethod; GetTimeMethod: TGetTimeMethod); var str : String; begin try SetTimeMethod(str);//這樣宣告對嗎? 上層的FUNCTION會自動將值傳入嗎 GetTimeMethod; finally MsgBox('Error!'); end; end; //Call this procedure ConfirmTime(SetTimeStr0('20030431'),GetTimeStr3()); 但是這裡會出現 Incompatible types... 要怎麼做啊?

引言: Hi william: Thanks your reply, but I still have some question..

procedure TMyDateTime.ConfirmTime(SetTimeMethod: TSetTimeMethod; GetTimeMethod: TGetTimeMethod);
var
  str : String;
begin
  try
     SetTimeMethod(str);//這樣宣告對嗎? 上層的FUNCTION會自動將值傳入嗎
Syntax correct but str is an undefined local variable         GetTimeMethod;
  finally
    MsgBox('Error!');
  end;    end;

//Call this procedure ConfirmTime(SetTimeStr0('20030431'),GetTimeStr3()); 但是這裡會出現 Incompatible types... 要怎麼做啊? procedure TMyDateTime.ConfirmTime(const time_str: string; SetTimeMethod: TSetTimeMethod; GetTimeMethod: TGetTimeMethod); {....} SetTimeMethod(time_str); {....} ConfirmTime('20030431',SetTimeStr0,GetTimeStr3());

Hi William: 再請問一下,我參考你的寫法實作後, 發現仍然會出現: Incompatible types:TSetMethod and String; 請問是那裡錯了? procedure TMyDateTime.ConfirmTime(const time_str: string; SetTimeMethod: TSetTimeMethod; GetTimeMethod: TGetTimeMethod); begin try SetTimeMethod(time_str); GetTimeMethod; finally MsgBox('The date is not valid date!'); end; end; ConfirmTime(('20030431'),GetTimeStr3()); Thanks Cherry

ConfirmTime('20030431',SetTimeStr0,GetTimeStr3);

Hi William: Sorry my careless... ConfirmTime('20030431', SetTimeStr0, GetTimeStr3); but error message Incompatible types 'regular procedure and method pointer' Thanks Cherry

Are SetTimeStr0, GetTimeStr3 methods of object? If not, I think you defined the wrong types:    T1BooleanMethod = function(const time_str : string):Boolean; TTestMethod = function():string;    

引言: Hi William: Sorry my careless... ConfirmTime('20030431', SetTimeStr0, GetTimeStr3); but error message Incompatible types 'regular procedure and method pointer' Thanks Cherry