c# 引用外部dll

c# 引用外部dll

2015-12-09 20:39:38 aaa_dai 阅读数 604 文章标签： DllImportsecurityA.dll 更多

 1,实现类

public class SecurityA {

//extern修饰符支持在外部实现方法
//外部修饰符的常见方法是在使用Interop 服务调入非托管代码时与 DllImport 属性一起使用；
//方法还必须声明为 static
[DllImport("securityA.dll")]
static extern IntPtr DeCode(IntPtr source, IntPtr key);
[DllImport("securityA.dll")]
static extern IntPtr EnCode(IntPtr source, IntPtr key);

public string enCrypt(string source,string key){

string output = string.Empty;
try
{

//转换为基本类型 IntPtr: 用于表示指针或句柄的平台特定类型。

IntPtr ptrIn = Marshal.StringToHGlobalAnsi(source);

IntPtr ptrInKey = Marshal.StringToHGlobalAnsi(key);

IntPtr ptrRtn = EnCode(ptrIn, ptrInKey);

output = Marshal.PtrToStringAnsi(ptrRtn);

}

catch(Exception e)

{

throw e;

}

return output;

}


public string deCrypt(string source, string key)

{

string strRtn = string.Empty;

try

{

IntPtr ptrIn = Marshal.StringToHGlobalAnsi(source);

IntPtr ptrInKey = Marshal.StringToHGlobalAnsi(key);

IntPtr ptrRtn = DeCode(ptrIn, ptrInKey);

strRtn = Marshal.PtrToStringAnsi(ptrRtn);

}

catch(Exception e)

{

throw e;

}


return strRtn;

}

}

2,调用 

1. string strKey = string.Empty ;

2. SecurityA sa = new SecurityA();

3.  

4. btnEncode.Click += delegate

5. {

6. //加密

7. string strCode = sa.enCrypt(txtBefore.EditValue.ToString(),strKey);

8. txtAfter.Text = strCode;

9. };

10.  

11. btnDecode.Click += delegate

12. {

13. //解密

14. string strCode = sa.deCrypt(txtAfter.EditValue.ToString(), strKey);

15. txtDecode.Text = strCode;

16. };

17.  

18. txtKey.EditValueChanged += delegate { strKey = txtKey.EditValue == null ? string.Empty : txtKey.EditValue.ToString(); };