<input type="hidden" name="__VIEWSTATE" id="__VIEWSTATE" value="/wEPDwUKMTkwNjc4NTIwMWRkyv4ncofW5vaWXdXRtXfXn3RYQR4=" />也就是說VIEwState中的值實際上都是通過一個hidden來保存的，hidden的name為__VIEWSTATE，那麼如果頁面上有另外一個控件的名稱也叫：__VIEWSTATE的話，會導致頁面出錯。 protected void Button1_Click(object sender, EventArgs e)
{
Test test = ViewState["VIEW_TEST"] as Test; if (test == null)
{ test = new Test();
} test[-1] = TextBox1.Text; ViewState["VIEW_TEST"] = test;
}[SerializableAttribute]class Test{ private IList list; public Test() { list = new ArrayList(); } public object this[int index] { get { if (index >= list.Count) { return null; } return list[index]; } set{ list.Add(value); } }}特別注意第一行的SerializableAttribute屬性，指定這個屬性後就代表此類是可以序列化的(具體序列化的過程都是由.Net內部進行的)，那麼我們就可以把此類放入VIEwState中了，如果沒有指定SerializableAttribute屬性的話，放入VIEwState時就會報錯。[SerializableAttribute]class Test : DataTable{ public Test() { DataColumn col = new DataColumn(); col.DataType = typeof(string); col.ColumnName = "name"; this.Columns.Add(col); } public object this[int index] { get{ if (index >= Rows.Count) { return null; } return Rows[index]["name"]; } set { DataRow row = NewRow(); row["name"] = value; Rows.Add(row); } }}那麼再把這個類放入VIEwState的話就會報錯：此頁的狀態信息無效，可能已損壞，主要是因為它的父類DataTable是不可序列化的，我們就需要把這個類改造成如下形式：[SerializableAttribute]class Test : DataTable, System.Runtime.Serialization.ISerializable public Test() { DataColumn col = new DataColumn(); col.DataType = typeof(string); col.ColumnName = "name"; this.Columns.Add(col); } public object this[int index] { get { if (index >= Rows.Count) { return null; } return Rows[index]["name"]; } set { DataRow row = NewRow(); row["name"] = value; Rows.Add(row); } } public Test(SerializationInfo info, StreamingContext context) { DataColumn col = new DataColumn(); col.DataType = typeof(string); col.ColumnName = "name"; this.Columns.Add(col); ArrayList list = info.GetValue("list", typeof(ArrayList)) as ArrayList; foreach (string value in list) { DataRow row = NewRow(); row["name"] = value; Rows.Add(row); } } public void GetObjectData(SerializationInfo info, StreamingContext context) { ArrayList list = new ArrayList(); foreach (DataRow row in this.Rows) { list.Add(row["name"]); } info.AddValue("list", list); }}1、實現ISerializable接口
