如何在一個十六進制值中合並 4 個無符號字符數組元素？

Question

我有一個由 4 個 unsigned char 類型元素組成的數組。 如何將這些合並為一個十六進制值？ 我需要將此值轉換為 IEE754 值。

例如unsigned char arr[]={0x41,0xD9,0xD4,0x03}

預期o/p： 0x41D9D403

Answer 1

unsigned long hex_val = ((unsigned long)arr[0] << 24) | ((unsigned long)arr[1] << 16) | ((unsigned long)arr[2] << 8) | ((unsigned long)arr[3]);