最近一项目中要求显示网络流量，而且必须使用C#。
事实上，调用 IpHlpApi.dll 的 GetIfTable API 可以轻易获得网络信息和网络流量。只是要在C#中实现还是比较复杂。
先看看怎么定义该 API
事实上，调用 IpHlpApi.dll 的 GetIfTable API 可以轻易获得网络信息和网络流量。只是要在C#中实现还是比较复杂。
先看看怎么定义该 API
[DllImport("IpHlpApi.dll")] extern static public uint GetIfTable(byte[] pIfTable, ref uint pdwSize, bool bOrder);本来想把 pIfTable 定义为 IntPtr，但是这样的结果是，获取的信息是错误的（直到现在都不知是什么原因）。
但显然定义为 byte[] 是不能直接使用的。幸好在 Google Code Search 找到了三个类：
CustomtMarshaler.csusing System;using System.IO;using System.Collections;using System.Reflection;using System.Runtime.InteropServices;using System.Threading;namespace Lemony.SystemInfo
{
/**//// <summary> /// CustomMarshaler class implementation.
/// </summary> public abstract class CustomMarshaler { Fields#region Fields // The internal buffer internal byte[] data; private MemoryStream stream; private BinaryReader binReader; private BinaryWriter binWriter; #endregion constructors#region constructors public CustomMarshaler() { } #endregion public methods#region public methods public void Deserialize() { if (data != null) { if (binReader != null) { binReader.Close(); stream.Close(); } // Create a steam from byte array stream = new MemoryStream(data); binReader = new BinaryReader(stream, System.Text.Encoding.Unicode); ReadFromStream(binReader); binReader.Close(); } } public void Serialize() { if (data != null) { stream = new MemoryStream(data); binWriter = new BinaryWriter(stream, System.Text.Encoding.Unicode); WriteToStream(binWriter); binWriter.Close(); } } public int GetSize() { int size = 0; FieldInfo[] fields = this.GetType().GetFields(BindingFlags.Public | BindingFlags.Instance); foreach (FieldInfo field in fields ) { if (field.FieldType.IsArray) { size += GetFieldSize(field); } else if (field.FieldType == typeof(string)) { size += GetFieldSize(field)*2; } else if (field.FieldType.IsPrimitive) { size += Marshal.SizeOf(field.FieldType); } } return size; } #endregion properties#region properties public byte[] ByteArray { get { return data; } } #endregion virtual and protected methods#region virtual and protected methods public virtual void ReadFromStream(BinaryReader reader) { object[] param = null; // Get all public fields FieldInfo[] fields = this.GetType().GetFields(BindingFlags.Public | BindingFlags.Instance); // Loop through the fields foreach(FieldInfo field in fields) { // Retrieve the read method from ReadMethods hashtable MethodInfo method = (MethodInfo)MarshallingMethods.ReadMethods[field.FieldType]; if (field.FieldType.IsArray) { Type element = field.FieldType.GetElementType(); if (element.IsValueType && element.IsPrimitive) { if ((element == typeof(char)) || element == typeof(byte)) { param = new object[1]; param[0] = GetFieldSize(field); field.SetValue(this, method.Invoke(reader, param)); } else // any other value type array { param = new object[2]; param[0] = reader; param[1] = GetFieldSize(field); field.SetValue(this, method.Invoke(null, param)); } } else // array of sub structures { int size = GetFieldSize(field); method = (MethodInfo)MarshallingMethods.ReadMethods[typeof(CustomMarshaler)]; Array objArray = Array.CreateInstance(element, size); for(int i=0;i<size;i++) { objArray.SetValue(Activator.CreateInstance(element), i); method.Invoke(objArray.GetValue(i), new object[]); } field.SetValue(this, objArray); } } else if (field.FieldType == typeof(string)) { param = new object[2]; param[0] = reader; param[1] = GetFieldSize(field); field.SetValue(this, method.Invoke(null, param)); } else if (field.FieldType.IsValueType && field.FieldType.IsPrimitive)// regular value type { field.SetValue(this, method.Invoke(reader, null)); } else //process substructure { CustomMarshaler subStruct = (CustomMarshaler)Activator.CreateInstance(field.FieldType); subStruct.ReadFromStream(reader); } } } public virtual void WriteToStream(BinaryWriter writer) { object[] param = null; FieldInfo[] fields = this.GetType().GetFields(BindingFlags.Public | BindingFlags.Instance); foreach(FieldInfo field in fields) { // Check if we have any value object value = field.GetValue(this); MethodInfo method = (MethodInfo)MarshallingMethods.WriteMethods[field.FieldType]; if (field.FieldType.IsArray) { Type element = field.FieldType.GetElementType(); if (element.IsValueType && element.IsPrimitive) { //method.Invoke(writer, new object[] ); Array arrObject = (Array)field.GetValue(this); param = new object[2]; param[0] = writer; param[1] = arrObject; method.Invoke(null, param); } else { //Get field size int size = GetFieldSize(field); //Get WriteToStream method method = (MethodInfo)MarshallingMethods.WriteMethods[typeof(CustomMarshaler)]; Array arrObject = (Array)field.GetValue(this); for(int i=0;i<size;i++) { method.Invoke(arrObject.GetValue(i), new object[]); } } } else if (field.FieldType == typeof(string)) { param = new object[3]; param[0] = writer; param[1] = field.GetValue(this); param[2] = GetFieldSize(field); method.Invoke(null, param); } else if (field.FieldType.IsValueType && field.FieldType.IsPrimitive)// regular value type { method.Invoke(writer, new object[] ); } } } protected int GetFieldSize(FieldInfo field) { int size = 0; CustomMarshalAsAttribute attrib = (CustomMarshalAsAttribute)field.GetCustomAttributes(typeof(CustomMarshalAsAttribute), true)[0]; if (attrib != null) { if (attrib.SizeField != null)&n