我tyring将C#字符串传递给C dll函数,它假设加密它。不幸的是,它根本就没有。调用该函数后,该字符串仍然相同。调用c改变传递参数在C中的dll函数#
C函数:
#include <stdio.h>
#include <stdlib.h>
extern "C"{
__declspec(dllexport) void Encrypt(char *plainText,long height,long inputLength)
{
unsigned char *encryptedText=(unsigned char*)malloc(sizeof(plainText));
unsigned char **cipherArray;
cipherArray=(unsigned char**)malloc(height*sizeof(unsigned char *));
for(long i=0; i<height; i++)
{
cipherArray[i]=(unsigned char*)malloc(inputLength*sizeof(char));
for (long j=0; j<inputLength ; j++)
cipherArray[i][j]='#';
}
bool addRow=true;
long row=0;
long column = 0;
long arrayIterator = 0;
while(arrayIterator<inputLength){
cipherArray[row][column] = plainText[arrayIterator];
column++;
if(addRow)row++;
else row--;
if (row >= height)
{
row--;
row--;
addRow=false;
}
else if (row < 0)
{
row++;
row++;
addRow = true;
}
arrayIterator++;
}
long iterator=0;
for (long i=0; i< height; i++)
for(long j=0; j<inputLength;j++){
if(cipherArray[i][j]!='#'){
encryptedText[iterator]=cipherArray[i][j];
iterator++;
}
}
long j=0;
while(j<inputLength){
plainText[j]=encryptedText[j];
printf("%c",encryptedText[j]);
j++;
}
for(long i=0; i<height; i++)
free(cipherArray[i]);
free(cipherArray);
cipherArray = NULL;
}
}
含C#类:
namespace RailFenceCipher
{
public class CCipher
{
[DllImport("Win32Project3.dll", EntryPoint = "Encrypt", CallingConvention = CallingConvention.Cdecl, CharSet = CharSet.Ansi)]
public static extern void Encrypt([MarshalAs(UnmanagedType.LPStr)] string plainText, long height, long inputLength);
}
}
,并呼吁功能:
private void cipherC()
{
string plainText = this.fileInput;
Console.WriteLine("=== C# test, using IntPtr and Marshal ===");
CCipher.dllprint();
CCipher.Encrypt(plainText, this.height, this.fileInput.Length);
this.fileOutputC = plainText;
Console.WriteLine("=== END ===");
}
呼叫后
,明文没有改变。
请注意,malloc(sizeof(plainText))只会分配4或8个字节(取决于您构建的是32位还是64位软件)。 – elgonzo
继续了@elgonzo说的话,你可能想'malloc(strlen(plainText))' –
@MarkkuK。不,它是malloc(inputLength) –