关于C#：指针算术对我来说还不清楚

Pointer arithmetic isn't clear to me

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我有要在其中增加指针的代码。但是编译器不喜欢我的表达。这是代码：

1 2	int * p_int[5]; p_int++;

编译器给出错误：

lvalue required as increment operand p_int++;

我认为p_int++;等同于p_int[++i]

相关讨论

您应该使用数组指针

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int arr_int[5] = {4,5,6,7,8};
int (*p_int)[5];
p_int = &arr_int;
p_int++; // p_int++; jumps forward 5 places in memory. (5 x sizeof(int))
// to iterate over the array elements do for(int i =0;i<5;i++){ (*p_int)[i];}

您可能正在寻找：

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int ar[5] = {2,3,4,6,7}; // an int array
int * p; // a int pointer
p = ar; // attach the array to pointer, an array is always an array of pointers so p = &ar; gives a error.
for(i=0;i<5;i++){printf("%d\
",*p++);} // dereference the *p and add 1 to the address the p holds as value.

。

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#include <stdlib.h>
#include <stdio.h>

int main(){
int i = 0;

char arr[3][10] = { // double dimensional array.
{"Hello"},
{"Welcome"},
{"Good bye."},
};

char (*ptr)[10]; // array pointer.
ptr = arr; // assign array to pointer.
for( ; i < 3 ; i++ ){
// print memory address, and array value.
printf("%p : %s \
", (*ptr), (*ptr));
// jump to next array = current memory address + 9.
ptr++;
}
printf(" ======================= \
");
char second_arr[8] = { 'W','e','l','c','o','m','e'};
char (*second_ptr)[8]; // array pointer.
second_ptr = &second_arr; // assign array to pointer.

printf("memory address: %p txt: %s \
", (*second_ptr), (*second_ptr));

printf(" ======================= \
");

for(i = 0 ; i < 7 ; i++ ){
// print memory address, and array value.
printf("%p : %c \
", (*second_ptr), (*second_ptr)[i]);
// jump to next array = current memory address + 9.
}
return 0;
};

第二个例子。 // * Typedef数组指针* //

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int i = 0, ERROR = 1, CRASH = 5, GOOD = 6, BUG = 8;
char succes_text[3][60] = {
{"Awesome performance detected !!\
"},
{"Your system and program are performing a expected.\
"},
{"No problems detected, proceeding next task.\
"}
};
char error_text[3][60] = {
{"Undefined error detected, call the help-desk.\
"},
{"Warning, bad algorithmic behavior.\
"},
{"Program manager found a bug, save your work.\
"}
};

typedef char (*SUCCES_TEXT_TYPE)[60];
SUCCES_TEXT_TYPE SUCCES_TEXT = succes_text;

typedef char (*ERROR_TEXT_TYPE)[60];
ERROR_TEXT_TYPE ERROR_TEXT = error_text;

char * testfunc(int i, SUCCES_TEXT_TYPE s_txt, ERROR_TEXT_TYPE e_txt){
if(i == ERROR){ return (*e_txt);}
if(i == CRASH){ e_txt += 1; return (*e_txt);}
if(i == BUG){ e_txt += 2; return (*e_txt);}
if(i == GOOD){ return (*s_txt);}
return"";
}

int main(){

for(;i < 10; i++){
printf("%s",testfunc(i, SUCCES_TEXT, ERROR_TEXT));
}
return 0;
};
// END SECOND EXAMPLE.....