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re: "SQL Server不存在或访问被拒绝"问题的解决

dyp07 — Thu, 27 Sep 2007 02:00:00 GMT

只打SP3的补丁就可以可吗，而且是必须的是吗，那SP4还用打吗？

dyp07 2007-09-27 10:00 发表评论

re: C#程序实现动态调用DLL的研究(转载)

菜鸟一只 — Wed, 06 Jun 2007 05:52:00 GMT

代码中，object 0 是在if语句块中定义的局部变量，在最后return (object)0时已经超出了其作用域。该代码是否实现过？
public object Invoke(string lpFileName,string Namespace,string ClassName,string lpProcName,object[] ObjArray_Parameter)

{

try

{// 判断 MyAssembly 是否为空或 MyAssembly 的命名空间不等于要调用方法的命名空间，如果条件为真，就用 Assembly.Load 加载所需 DLL 作为程序集

if(MyAssembly==null||MyAssembly.GetName().Name!=Namespace)

MyAssembly=Assembly.Load(LoadDll(lpFileName));

Type[] type=MyAssembly.GetTypes();

foreach(Type t in type)

{

if(t.Namespace==Namespace&&t.Name==ClassName)

{

MethodInfo m=t.GetMethod(lpProcName);

if(m!=null)

{// 调用并返回

object o=Activator.CreateInstance(t);

return m.Invoke(o,ObjArray_Parameter);

}

else

System.Windows.Forms.MessageBox.Show(" 装载出错 !");

}

}

}

catch(System.NullReferenceException e)

{

System.Windows.Forms.MessageBox.Show(e.Message);

}

return (object)0;

}

菜鸟一只 2007-06-06 13:52 发表评论

re: C#程序实现动态调用DLL的研究(转载)[未登录]

Mon, 04 Jun 2007 12:33:00 GMT

"尝试读取或写入受保护的内存。这通常指示其他内存已损坏。"
我总是出现这个错误，能否帮忙看看……
在.net中的声明和调用如下
[DllImport("C:\\Dev-Cpp\\新建文件夹\\libProject1.dll", EntryPoint = "_ZN4Trie6insertEPc", CallingConvention = CallingConvention.ThisCall, CharSet = CharSet.Auto, SetLastError = true)]
public static extern void insert(IntPtr ths,ref String word);

[DllImport("C:\\Dev-Cpp\\新建文件夹\\libProject1.dll", EntryPoint = "_ZN4Trie9wordFoundEPc", CallingConvention = CallingConvention.ThisCall, CharSet = CharSet.Unicode, SetLastError = true)]
public static extern bool wordFound(IntPtr ths,ref String word);

[DllImport("C:\\Dev-Cpp\\新建文件夹\\libProject1.dll" )]
public static extern IntPtr CreateTrie(String word);

[DllImport("C:\\Dev-Cpp\\新建文件夹\\libProject1.dll")]
public static extern void DeleteTrie(IntPtr instance);

private void button4_Click(object sender, EventArgs e)
{
}
private void Form1_Load(object sender, EventArgs e)
{
StreamReader objReader = new StreamReader("C:\\1.txt");
string sLine = "";
ArrayList arrText = new ArrayList();
string s = "a";
IntPtr instancePtr = CreateTrie(s);
while (sLine != null)
{
sLine = objReader.ReadLine();
if (sLine != null)
{
string[] split = null;

int count = 0;

split = sLine.Split(new char[] { ' '});
foreach (string word in split)
{
count++;

}
for (int i = 0; i < count;i++ )
{
try
{
// string n_size = instancePtr.ToString();
// MessageBox.Show(n_size);
insert(instancePtr, ref split[i]);
DeleteTrie(instancePtr);

string ww = split[i];
MessageBox.Show(ww);

if (wordFound(instancePtr, ref ww))

MessageBox.Show("founded");
}
catch (Exception es)
{
MessageBox.Show(es.ToString());
}
}
}
}
objReader.Close();

}
我的dll源程序的头文件是这样的
#ifndef _DLL_H_
#define _DLL_H_

# define DLLIMPORT __declspec (dllexport)

#include
class Trie;
class TrieNonLeafNode {

public:
TrieNonLeafNode(char ch)
{
ptrs = new TrieNonLeafNode*;
letters = new char[2];
if (ptrs == 0 || letters == 0) {
return ;
}
leaf = false;
endOfWord = false;
*ptrs = 0;
*letters = ch;
*(letters+1) = '\0';
};
private:
bool leaf, endOfWord;
char *letters;
TrieNonLeafNode **ptrs;
friend class Trie;
};

class TrieLeafNode {

public:
TrieLeafNode(char* suffix){
leaf = true;
word = new char[strlen(suffix)+1];
if (word == 0) {
// cerr << "Out of memory2.\n";
// exit(-1);
return ;
}
strcpy(word,suffix);
};
private:
bool leaf;
char *word;
friend class Trie;
};
class Trie
{
public:

Trie(char *);

// void DLLIMPORT printTrie();
void DLLIMPORT insert(char*);
bool DLLIMPORT wordFound(char*);

private:
TrieNonLeafNode *root;
int notFound;
char prefix[80];
int position(TrieNonLeafNode*,char);
void addCell(char,TrieNonLeafNode*,int);
void createLeaf(char,char*,TrieNonLeafNode*);
// void printTrie(int,TrieNonLeafNode*,char*);

};

extern "C" DLLIMPORT Trie * CreateTrie(char * word);

extern "C" DLLIMPORT void DeleteTrie( Trie* instance );
#endif /* _DLL_H_ */

急切盼望你的回复，小妹刚出道阿，希望你能帮帮我。

玲 2007-06-04 20:33 发表评论