C语言 表达式必须具有整数类型

expression must have integral type

提问by Ogee Gee

I get that compilation error because of this line which intended to increase the pointer by 0x200 (to point to the next segment)

由于这一行打算将指针增加 0x200（指向下一段），因此我收到了编译错误

Flash_ptr = Flash_ptr + (unsigned char *) 0x200;

I'v seen thisbut I didn't use any illegal symbol!

我见过这个，但我没有使用任何非法符号！

P.S. The initialization of the pointer:

PS 指针的初始化：

unsigned char * Flash_ptr = (unsigned char *) 0x20000; 

回答by Paul R

You can't add two pointers. You can add an integer to a pointer, and you can subtract two pointers to get an integer difference, but adding two pointers makes no sense. To solve your problem therefore you just need to remove the cast:

你不能添加两个指针。可以将一个整数加到一个指针上，也可以减去两个指针得到一个整数差，但是两个指针相加是没有意义的。因此，要解决您的问题，您只需要删除演员表：

Flash_ptr = Flash_ptr + 0x200;

This increments Flash_ptrby 0x200 elements, but since Flash_ptris of type unsigned char *then this just translates to an increment of 0x200 bytes.

这会增加Flash_ptr0x200 个元素，但由于Flash_ptr是类型，unsigned char *所以这只是转换为 0x200字节的增量。

In order to make this part of a loop and check for an upper bound you would do something like this:

为了使这部分成为循环并检查上限，您将执行以下操作：

while (Flash_ptr < (unsigned char *)0x50000) // loop until Flash_ptr >= 0x50000
{
    // ... do something with Flash_ptr ...
    Flash_ptr += 0x200;
}

回答by Sourav Ghosh

You cannot addtwo pointers. What you can do is to incrementthe address held by the pointer. Remove the (unsigned char *)cast.

您不能添加两个指针。您可以做的是增加指针持有的地址。移除(unsigned char *)演员表。

If you're interested, read more about pointer arithmatic here.

如果您有兴趣，请在此处阅读有关指针算术的更多信息。