ViewFields是SPViewFieldCollection, 只能拿到interal name，要獲取中文的字段名，可以事先做一個internalName到title的轉換:

using System.collection;

SPSite site = new SPSite("url");

SPWeb web = site.OpenWeb();

SPList list = web.Lists[listname];

SPView listview = onelist.Views[view];

Hashtable internalToTitle = new Hashtable();

foreach(SPField field in list.Fields)
{
internalToTitle.Add(field.InternalName, field.Title);
}

輸出的時候轉換一下:
for（int j=0;j<listview.ViewFields）
{
output.write(internalToTitle[view.ViewFields[j]].ToString());
}