public static string ConvertFromListTojson<T>(IList<T> list, int total, string columnInfos) where T : class
{
string[] cols = columnInfos.Split(new char[]{','},StringSplitOptions.RemoveEmptyEntries);
StringBuilder sb = new StringBuilder(300);
sb.Append("{/"total/":");
sb.Append(total);
sb.Append(",/"rows/":");
sb.Append("[");
foreach (T t in list)
{
sb.Append("{");
foreach (string col in cols)
{
string name = "/"{0}/":/"{1}/",";
string value = getValue<T>(t, col);
value = value.Replace("/r/n", "//r//n");
sb.Append(string.Format(name, col, value));
}
if (cols.Length > 0)
{
int length = sb.Length;
sb.Remove(length - 1, 1);
}
sb.Append("},");
}
if (list.Count > 0)
{
int length2 = sb.Length;
sb.Remove(length2 - 1, 1);
}

sb.Append("]");
sb.Append("}");
return sb.ToString();
}
private static string getValue<T>(T t, string pname) where T : class
{
Type type = t.GetType();
PropertyInfo pinfo = type.GetProperty(pname);
if (pinfo != null)
{
object v = pinfo.GetValue(t, null);
return v != null ? v.ToString() : "";
}
else
{
throw new Exception("不存在属性" + pname);
}

}