如何在typedef结构中使用const int？

类似的东西：当你第一次创建它时，你可以设置它的常量值，而不是之后，因为它将在程序内存中。程序内存不能以这种方式改变。



      以下为原文

    Something like this:
    typedef struct{
         char const * const Name[2];
         const int MaxValue;
         const int Type;
         const int EppromLocation;
         const int NextID;
         const int PreviousID;
   } Parameters_t;
Parameters_t Parameter={ {{"abc"},{"def"}},1,2,3,4,5};
 
You can set the constant value when you first create it but not after since it will be in program memory.  Program memory cannot be changed in that way.

搜索：编译时间vs运行时。要添加：如果你正在修改它，那么它不能是常数。你可以指向一个常量内存，比如一个字符串。现在删除const直到它工作。如果它是一个数组，那么你仍然可以把它全部设置成一个，就像我之前的几篇文章。



      以下为原文

    Search: compile time vs runtime.
 
To add:
If you are modifying it then it can not be constant.  You can point to constant memory such as a string.
Remove the const for now until it is working.
 
If it is an array then you still can set it all up in one like I did a few posts ago.
 

谢谢你的快速回复。如果我想在源文件中使用多个寄存器呢？源文件出错



      以下为原文

    Thank you for quick reply. What if i want to use multiple registers in source file?
Header
   typedef struct{
         char const * const Name[2];
         const int MaxValue;
         const int Type;
         const int EppromLocation;
         const int NextID;
         const int PreviousID;
   } Parameters_t;
Parameters_t Parameter[5];
 
In source file
 Parameters_t MenuRegister[5];

void RegisterInit()
{
  
  MenuRegister[0]={{{"abc"},{"def"}},1,2,3,4,5};
}
 
I'm getting error
 
a.c:17: error: (195) expression syntax
a.c:17: error: (312) ";" expected
a.c:17: error: (285) no identifier in declaration
a.c:17: warning: (374) missing basic type; int assumed

此语法只能用于初始化，而不应用于赋值。它需要成为宣言的一部分。



      以下为原文

   
 
This syntax can only be used in initialization, not in an assignment.  It needs to be part of the declaration.

该结构将不会放置在程序内存中。这不是永久的。



      以下为原文

   
 
That structure will not be placed in program memory.  It is not const.
 

你必须在编译时设置数组/Stutt。你仍然在使用常量运行时。你可以这样做一个数组：PosialPyt p [3 ]＝{{“abc”，“DEF”}，1，2，3，4，5 }，{“GHI”，“JKL”}，6，7，8，9，10 }，{{“MNO”，“PQR”}，11，12，13，14，15}；



      以下为原文

    You have to set the array/struct at compile time.
You are still using runtime on constants.
 
 
You can do an array like this:
Parameter_t p[3]=
{
    {{"abc","def"},1,2,3,4,5},
    {{"ghi","jkl"},6,7,8,9,10},
    {{"mno","pqr"},11,12,13,14,15}
};
 
 

设置一次，忘记一次。



      以下为原文

    Set once and forget.
 

如果你这样改变你的结构，它们都是conist.Type，const结构{{}；在常量内存中：



      以下为原文

    If you change your structure heading like this, they are all then constants.
typedef const struct{};
 
 
In constant memory:
const Parameter_t p[3]=
{
    {{"abc","def"},1,2,3,4,5},
    {{"ghi","jkl"},6,7,8,9,10},
    {{"mno","pqr"},11,12,13,14,15}
};
 

大括号改变范围。



      以下为原文

    Curly braces change the scope.
 

放入程序存储器：



      以下为原文

    To place into program memory:
typedef const struct {
  const char *Name[2];
  int MaxValue;
  int Type;
  int EppromLocation;
  int NextID;
  int PreviousID;
} Parameters_t;
 
Parameters_t Parameter[5] = {
  {{"abc","def"},1,2,3,4,5},
  {{"ghi","jkl"},6,7,8,9,0},
  {{"mno","pqr"},1,2,3,4,5},
  {{"stu","vwx"},6,7,8,9,0},
  {{"foo","bar"},1,2,3,4,5}
};

很好的回答谢谢！第一个问题我可以宣布它们是秘密的。原因是我想读取每个变量名来理解它所做的每件事。例如：等等。它帮助我读取变量名。第二个问题，我可以用不同的寄存器吗？最后一个问题，如果我将包含在一个非静态的值示例中，我会在初始化中一起声明它们吗？



      以下为原文

    Nice answer thanks! First question can i declare them separetaly. The reason is that i want to read each variable name for understanding what everything its doing.
 
Example:
 

Parameters_t Parameter[1].Name = {"abc","def"};

and so on.It Helps me to read variable name.
Second question can i use different registers for each one?

Parameters_t Parameter[1] = { {{"abc","def"},1,2,3,4,5};
Parameters_t Parameter[2] = { {{"abc","def"},1,2,3,4,5};
Parameters_t Parameter[3] = { {{"abc","def"},1,2,3,4,5};

 
And last qustion, what if i i will include inside a non static value example

 typedef const struct {
  const char *Name[2];
  int MaxValue;
  int Type;
  int EppromLocation;
  int NextID;
  int PreviousID;
  union
  {
      unsigned int Value;
      unsigned char bytes[2];
  }SetValues;
 
} Parameters_t;

 
Can i declare them together in initialize?

作为声明的一部分，您只能将整个结构初始化一次。你不能把它拆开。我不知道你的意思是“把它们一起声明为初始化”。



      以下为原文

    You can only initialize the entire structure one time as part of the declaration.  You can't split it up.  I don't know what you mean by "declare them together in initialize".

它可以帮助我一起读取变量，以便于如果需要更改，示例：所以我需要并列放置const和unconst变量。



      以下为原文

    It helps me to read variables all together, for make it easy if i need to make a change;
Example:
 Register[0].PreviousID=2;
    Register[0].Name[0]="AAAAA";
    Register[0].Name[1]="asdwwew";
    Register[0].MaxValue=100;
    Register[0].MinValue=0;
    Register[0].SetValues.Value=10;
    Register[0].NextID=1;
 
So i need to place const and non const variables side by side.

如果需要，可以在结构中混合const和unconst成员。但是在const成员中设置一个值的唯一方法是声明它。



      以下为原文

    You can mix const and non-const members in a struct if you want.  But the only way to set a value in a const member is when it's declared.

我认为这里有一个失败来掌握初始化代码和可执行代码之间的区别。



      以下为原文

    I think there is a failure here to grasp the difference between initialisation code and executable code.
 
 

那么，QusiTo是，当它们被声明时，我可以设置它们两者的值（const和const）吗？const值也应该在数组内吗？我可以用变量的名字来区分它们吗？就像我的例子一样，我如何在相同的Type结构中使用const和unconst？



      以下为原文

    Ok then the qustion is can i set values both of them (const and non const)when they are declared?
 
Also const values should be inside an array? Can i separate them with the name of its variable? like my example.
Also how i will use const and non const inside same typedef struct?