private void FormMain_Load(object sender, EventArgs e)
{
    ShareDirec();
}

public void ShareDirec() { 
    ManagementClass management =new ManagementClass("Win32_share");

    ManagementBaseObject inParams = management.GetMethodParameters("Create");
    ManagementBaseObject outParams;

    string strPath = @"Z:\";
    string strName = "网络磁盘Z";
    inParams["Name"] = strName;
    inParams["Path"] = strPath;
    inParams["Type"] = 0x0;

    outParams = management.InvokeMethod("Create", inParams, null);


    if ((uint)(outParams.Properties["ReturnValue"].Value) != 0)
    {
        txtLog.AppendText(string.Format("【{0}】共享失败", strPath));
        return;
    }
    else {
        string strLog = string.Format("已将路径【{0}】设置为共享目录，共享名称为【{1}", strPath, strName);
        txtLog.AppendText(strLog);
    }
}