我的程序:
class Program {
[DllImport("libiconvD.dll", CallingConvention = CallingConvention.Cdecl)]
public static extern IntPtr libiconv_open([MarshalAs(UnmanagedType.LPStr)]
string tocode,
[MarshalAs(UnmanagedType.LPStr)]
string fromcode);
[DllImport("libiconvD.dll", CallingConvention = CallingConvention.Cdecl)]
static extern ulong libiconv(IntPtr icd,
ref StringBuilder inbuf, ref ulong inbytesleft,
out StringBuilder outbuf, out ulong outbytesleft);
[DllImport("libiconvD.dll", CallingConvention = CallingConvention.Cdecl)]
static extern int libiconv_close(IntPtr icd);
static void Main(string[] args) {
var inbuf = new StringBuilder("Rule(s): Global Tag – Refer to Print Rules – General Requirements");
ulong inbytes = (ulong)inbuf.Length;
ulong outbytes = inbytes;
StringBuilder outbuf = new StringBuilder((int)outbytes);
IntPtr icd = libiconv_open("utf8", "windows-1252");
var rcode1 = libiconv(icd, ref inbuf, ref inbytes, out outbuf, out outbytes);
Debug.WriteLine(rcode1);
var rcode2 = libiconv_close(icd);
Debug.WriteLine(rcode2);
}//Main()
}//Program CLASS
第一次调用 libiconv_open() 有效并返回指向 icd 的指针。 当第二次调用 libiconv() 运行时，它会在 icd 指针上发生访问冲突。
这里是被调用的 C 代码:
size_t iconv (iconv_t icd,
ICONV_CONST char* * inbuf, size_t *inbytesleft,
char* * outbuf, size_t *outbytesleft)
{
conv_t cd = (conv_t) icd;
if (inbuf == NULL || *inbuf == NULL)
return cd->lfuncs.loop_reset(icd,outbuf,outbytesleft);
else
return cd->lfuncs.loop_convert(icd,
(const char* *)inbuf,inbytesleft,
outbuf,outbytesleft);
}
似乎无法访问指针指向的结构中定义的函数。是否需要对返回的指针执行一些特殊操作才能在后续调用中使用。
谢谢
最佳答案
事实证明，C# 不需要使用 libiconv 库。只需使用 Encoding 类即可。
static void Main(string[] args) {
UTF8Encoding utf8 = new UTF8Encoding();
Encoding w1252 = Encoding.GetEncoding(1252);
string inbuf = "Rule(s): Global Tag – Refer to Print Rules – General Requirements";
byte[] bytearray = utf8.GetBytes(inbuf);
byte[] outbytes = Encoding.Convert(utf8, w1252, bytearray);
Debug.WriteLine("*************************");
Debug.WriteLine(String.Format(" Input: {0}", inbuf));
Debug.WriteLine(String.Format(" Output: {0}", utf8.GetString(outbytes)));
Debug.WriteLine("*************************");
}//Main()
*************************
Input: Rule(s): Global Tag – Refer to Print Rules – General Requirements
Output: Rule(s): Global Tag – Refer to Print Rules – General Requirements
*************************
关于c# - 为什么后续调用时不能使用IntPtr，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/55910528/