我下载最新的zedgraph library,里面的Readme是下面的的.lz你的程序的.net framework是不是高于3.5了?
*****************************************************************************************
For easy distribution, this archive provides the dll form of ZedGraph only.
This distribution of the ZedGraph source code includes two versions:
Version 4.6.x is the .Net 1.1 compatible version
Version 5.1.x is the .Net 2.0 compatible version
Complete source code for ZedGraph is available on sourceforge here:
http://sourceforge.net/projects/zedgraph/
A wiki providing help, samples, etc. is available here:
http://zedgraph.org
A tutorial on using ZedGraph is available here:
http://www.codeproject.com/csharp/zedgraph.asp