未将对象引用设置到对象的实例

versacexw 2008-12-01 10:58:49



Page_Error
未将对象引用设置到对象的实例。 Application Error 在 ESRI.ArcGIS.ADF.Web.UI.WebControls.MapTips.a() 在 ESRI.ArcGIS.ADF.Web.UI.WebControls.MapTips.c() 在 ESRI.ArcGIS.ADF.Web.UI.WebControls.MapTips.Render(HtmlTextWriter writer) 在 System.Web.UI.Control.RenderControlInternal(HtmlTextWriter writer, ControlAdapter adapter) 在 System.Web.UI.Control.RenderControl(HtmlTextWriter writer, ControlAdapter adapter) 在 System.Web.UI.Control.RenderControl(HtmlTextWriter writer) 在 System.Web.UI.Control.RenderChildrenInternal(HtmlTextWriter writer, ICollection children) 在 System.Web.UI.Control.RenderChildren(HtmlTextWriter writer) 在 System.Web.UI.HtmlControls.HtmlForm.RenderChildren(HtmlTextWriter writer) 在 System.Web.UI.HtmlControls.HtmlContainerControl.Render(HtmlTextWriter writer) 在 System.Web.UI.HtmlControls.HtmlForm.Render(HtmlTextWriter output) 在 System.Web.UI.Control.RenderControlInternal(HtmlTextWriter writer, ControlAdapter adapter) 在 System.Web.UI.Control.RenderControl(HtmlTextWriter writer, ControlAdapter adapter) 在 System.Web.UI.Control.RenderControl(HtmlTextWriter writer) 在 System.Web.UI.HtmlControls.HtmlForm.RenderControl(HtmlTextWriter writer) 在 ASP.default_aspx.__Render__control1(HtmlTextWriter __w, Control parameterContainer) 位置 c:\WINDOWS\Microsoft.NET\Framework\v2.0.50727\Temporary ASP.NET Files\expresswaymanager\733c0d6c\fb136bc4\App_Web_g8ox4e3a.4.cs:行号 0 在 System.Web.UI.Control.RenderChildrenInternal(HtmlTextWriter writer, ICollection children) 在 System.Web.UI.Control.RenderChildren(HtmlTextWriter writer) 在 System.Web.UI.Control.Render(HtmlTextWriter writer) 在 System.Web.UI.Page.Render(HtmlTextWriter writer) 在 System.Web.UI.Control.RenderControlInternal(HtmlTextWriter writer, ControlAdapter adapter) 在 System.Web.UI.Control.RenderControl(HtmlTextWriter writer, ControlAdapter adapter) 在 System.Web.UI.Control.RenderControl(HtmlTextWriter writer) 在 System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint)




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年轻时追求 2009-05-17
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看看在response前加上这个System.Web.HttpContext.Current.
YODA360 2009-05-05
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这个查看为null的方法是怎么实现的 就是怎么查啊 我不太会 我一样的问题
jizhaoliang 2009-04-02
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ai
versacexw 2008-12-03
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App_Web_3if4wu9k.dll!ASP.default_aspx.__Render__control1(System.Web.UI.HtmlTextWriter __w = {System.Web.UI.HtmlTextWriter}, System.Web.UI.Control parameterContainer = {ASP.default_aspx}) + 0x94 字节


这是错误提示的调用外部堆栈的外部代码，大家帮忙看看到底什么错误啊，怎么修改啊？？太郁闷了！！或者哪位好心人留个邮箱，我把项目发给你帮我看看呀，谢谢！！！
versacexw 2008-12-03
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下面是提示出错的反汇编源码

00000000 push ebp
00000001 mov ebp,esp
00000003 push edi
00000004 push esi
00000005 push ebx
00000006 sub esp,34h
00000009 xor eax,eax
0000000b mov dword ptr [ebp-10h],eax
0000000e xor eax,eax
00000010 mov dword ptr [ebp-1Ch],eax
00000013 mov edi,ecx
00000015 mov esi,edx
00000017 cmp dword ptr ds:[062B8A90h],0
0000001e je 00000025
00000020 call 714E26DE
00000025 nop
00000026 mov edx,dword ptr ds:[024171F8h]
0000002c mov ecx,esi
0000002e mov eax,dword ptr [ecx]
00000030 call dword ptr [eax+00000090h]
00000036 nop
00000037 mov ecx,dword ptr [ebp+8]
0000003a mov eax,dword ptr [ecx]
0000003c call dword ptr [eax+00000100h]
00000042 mov ebx,eax
00000044 mov ecx,ebx
00000046 xor edx,edx
00000048 mov eax,dword ptr [ecx]
0000004a call dword ptr [eax+60h]
0000004d mov ebx,eax
0000004f mov edx,esi
00000051 mov ecx,ebx
00000053 mov eax,dword ptr [ecx]
00000055 call dword ptr [eax+000000ECh]
0000005b nop
0000005c mov edx,dword ptr ds:[023E0EC0h]
00000062 mov ecx,esi
00000064 mov eax,dword ptr [ecx]
00000066 call dword ptr [eax+00000090h]
0000006c nop
0000006d mov ecx,dword ptr [ebp+8]
00000070 mov eax,dword ptr [ecx]
00000072 call dword ptr [eax+00000100h]
00000078 mov ebx,eax
0000007a mov ecx,ebx
0000007c mov edx,1
00000081 mov eax,dword ptr [ecx]
00000083 call dword ptr [eax+60h]
00000086 mov ebx,eax
00000088 mov edx,esi
0000008a mov ecx,ebx
0000008c mov eax,dword ptr [ecx]
0000008e call dword ptr [eax+000000ECh]
00000094 nop /* 提示这行出错的，不知道什么原因，单步调试的时候没有这个错误，直接运行就有了，很奇怪 */
00000095 mov edx,dword ptr ds:[024171FCh]
0000009b mov ecx,esi
0000009d mov eax,dword ptr [ecx]
0000009f call dword ptr [eax+00000090h]
000000a5 nop
dq512000 2008-12-03
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打断点跟踪下吧。。。
看看哪个值为NULL。。。
versacexw 2008-12-03
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我就是在最后的这个事件里出错的，就一个语句，看不出来错误啊
protected void btnBack_Click(object sender, EventArgs e)
{
Response.Redirect("~/Default.aspx");
}
moluotuo 2008-12-01
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你究竟是那一步操作除了问题，应当到那个事件里面找错
versacexw 2008-12-01
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/// <summary>
/// 计算事故等级
/// </summary>
/// <param name="DeathNum"></param>
/// <param name="InjuryNum"></param>
/// <param name="marVehicleNum"></param>
/// <returns></returns>
private string CalculateEvent(string DeathNumClass, string InjuryNumClass, string marVehicleNumClass)
{
string eventdegree = null;

if (DeathNumClass == "0人" && InjuryNumClass == "0人" && (marVehicleNumClass == "0辆" || marVehicleNumClass == "1--2辆"))
{
eventdegree = "一般事故";
}
else if (DeathNumClass == "0人" && InjuryNumClass == "1--2人" || marVehicleNumClass == "3--10辆")
{
eventdegree = "较大事故";
}
else if (DeathNumClass == "1--2人" || InjuryNumClass == "3--10人" || marVehicleNumClass == "10--20辆")
{
eventdegree = "重大事故";
}
else if (DeathNumClass == "大于3人" || InjuryNumClass == "大于10人" || marVehicleNumClass == "大于20辆")
{
eventdegree = "特大事故";
}
else
{
// throw new Exception("事故输入数据不正确。");
}
return eventdegree;
}
protected void rblDegree_SelectedIndexChanged(object sender, EventArgs e)
{
string eventDegree = CalculateEvent(rblDeathNum.SelectedValue, rblInjuryNum.SelectedValue, rblVehicleHarming.SelectedValue);
ddlEventDegree.SelectedValue = eventDegree;
if (ddlEventKind.SelectedIndex == 1)
{
ddlEventDegree.SelectedIndex = 3;
}
}
protected void ddlChemistryDangerKind_SelectedIndexChanged(object sender, EventArgs e)
{
}
protected void btnGetDangerImpact_Click(object sender, EventArgs e)
{
txtDangerImpactRange.Text = "2";
}
protected void btnBack_Click(object sender, EventArgs e)
{
Response.Redirect("~/Default.aspx");
}
[/code]
versacexw 2008-12-01
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这个是另一个页面的代码
[code=C#]
using System;
using System.Data;
using System.Data.SqlClient;
using System.Configuration;
using System.Collections;
using System.Collections.Generic;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;

public partial class EventDeal_AddEvent : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
((Menu)Master.FindControl("TitleMenu")).Visible = false;
}
protected void srcEventAlarms_Inserted(object sender, SqlDataSourceStatusEventArgs e)
{
int eventID =Convert.ToInt32(e.Command.Parameters["@ID"].Value);
if (Session["EventID"] == null)
Session.Add("EventID", eventID);
lblAddResult.Text = eventID.ToString() + "号报警记录完毕!";

}
protected void srcEventAlarms_Inserting(object sender, SqlDataSourceCommandEventArgs e)
{
SqlParameter eventID = new SqlParameter("@ID", SqlDbType.Int);
eventID.Direction = ParameterDirection.Output;
e.Command.Parameters.Add(eventID);

SqlParameter state = new SqlParameter("@State", "未处理");
e.Command.Parameters.Add(state);

if (ddlEventDegree.SelectedIndex == 1)
{
SqlParameter DangerID = new SqlParameter("@DangerID", ddlDangerName.SelectedItem.Value);
e.Command.Parameters.Add(DangerID);
}
else
{
SqlParameter dangerID = new SqlParameter("@DangerID", null);
e.Command.Parameters.Add(dangerID);
}

}
protected void txtAlarmDateTime_Load(object sender, EventArgs e)
{
((TextBox)sender).Text = DateTime.Now.ToString();
((TextBox)sender).ReadOnly = true;
}
protected void txtReceiver_Load(object sender, EventArgs e)
{
((TextBox)sender).Text =Context.User.Identity.Name;
((TextBox)sender).ReadOnly = true;
}
protected void DropDownList1_Load(object sender, EventArgs e)
{
int RoadLength = 114;
for (int i = 0; i <= RoadLength; i++)
((DropDownList)sender).Items.Add(Convert.ToString(i));
}
protected void DropDownList2_Load(object sender, EventArgs e)
{
for (int i = 0; i < 1000; i++)
((DropDownList)sender).Items.Add(Convert.ToString(i));
}
protected void CheckBox1_CheckedChanged(object sender, EventArgs e)
{
ddlFireVehicleNum.Enabled = ((CheckBox)sender).Checked;
}


protected void btnAdd_Click(object sender, EventArgs e)
{
srcEventAlarms.Insert();
}
protected void ddlEventKind_SelectedIndexChanged(object sender, EventArgs e)
{
if (((DropDownList)sender).SelectedIndex == 1)
{
divDanger.Style["display"] = "block";
ddlEventDegree.SelectedIndex = 3;
List<string> dangerslist = new List<string>();
dangerslist.Add("爆炸品");
dangerslist.Add("压缩气体和液化气体");
dangerslist.Add("易燃液体");
dangerslist.Add("易燃固体");
dangerslist.Add("自燃物品和遇湿易燃物品");
dangerslist.Add("氧化剂和有机过氧化物");
dangerslist.Add("毒害品和腐蚀品");
dangerslist.Add("其它危险品");
ddlChemistryDangerKind.DataSource = dangerslist;
ddlChemistryDangerKind.DataBind();
}
else
{
divDanger.Style["display"] = "none";
}

}
protected void ddlEventDegree_SelectedIndexChanged(object sender, EventArgs e)
{
if (ddlEventKind.SelectedIndex ==1)
{
ddlEventDegree.SelectedIndex=3;
}
}
moluotuo 2008-12-01
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打断点调试，跟踪一下，看看那个对象还为null 就调用它的方法了
versacexw 2008-12-01
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void OverviewMap_Panel_PanelExpanded(object sender, EventArgs args)
{
FloatingPanel ovPanel = Page.FindControl("OverviewMap_Panel") as FloatingPanel;
if (ovPanel != null)
{
OverviewMap ov = ovPanel.FindControl("OverviewMap1") as OverviewMap;
if (ov != null)
{
ov.Enabled = true;
ov.Refresh();
ovPanel.CallbackResults.CopyFrom(ov.CallbackResults);
}
}
}

void OverviewMap_Panel_PanelCollapsed(object sender, EventArgs args)
{
FloatingPanel ovPanel = Page.FindControl("OverviewMap_Panel") as FloatingPanel;
if (ovPanel != null)
{
OverviewMap ov = ovPanel.FindControl("OverviewMap1") as OverviewMap;
if (ov != null)
ov.Enabled = false;
}
}

#region ICallbackEventHandler Members
private string _callbackArg;

//public string GetCallbackResult()
//{
// throw new Exception("The method or operation is not implemented.");
//}

void ICallbackEventHandler.RaiseCallbackEvent(string eventArgument)
{
_callbackArg = eventArgument;
}

string ICallbackEventHandler.GetCallbackResult()
{
return RaiseCallbackEvent(_callbackArg);
}

#endregion

#region ICallbackHandler

public virtual string RaiseCallbackEvent(string responseString)
{
// break out the responseString into a querystring
Array keyValuePairs = responseString.Split("&".ToCharArray());
NameValueCollection m_queryString = new NameValueCollection();
string[] keyValue;
string response = "";
if (keyValuePairs.Length > 0)
{
for (int i = 0; i < keyValuePairs.Length; i++)
{
keyValue = keyValuePairs.GetValue(i).ToString().Split("=".ToCharArray());
m_queryString.Add(keyValue[0], keyValue[1]);
}
}
else
{
keyValue = responseString.Split("=".ToCharArray());
if (keyValue.Length > 0)
m_queryString.Add(keyValue[0], keyValue[1]);
}
// isolate control type and mode
string controlType = m_queryString["ControlType"];
string eventArg = m_queryString["EventArg"];
if (controlType == null) controlType = "Map";
switch (controlType)
{
case "Map":
// request is for the map control
if (eventArg == "MapIdentify")
{
// Identify
if (identify != null)
{
identify.Map = Map1; // make sure it is current
response = identify.Identify(m_queryString);
}
}
else if (eventArg == "CloseOutApplication")
{
// Close out session and quit application
IServerContext context;
for (int i = 0; i < Session.Count; i++)
{
context = Session[i] as IServerContext;
if (context != null)
{
context.RemoveAll();
context.ReleaseContext();
}
}
response = "SessionClosed";
Session.RemoveAll();
response = ConfigurationManager.AppSettings["CloseOutUrl"];
if (response == null || response.Length == 0) response = "ApplicationClosed.aspx";
}
else if (eventArg == "GetCopyrightText")
{
System.Text.StringBuilder sb = new System.Text.StringBuilder();
sb.AppendFormat("///:::{0}:::innercontent:::","CopyrightTextContents");
int sbLength = sb.Length;
sb.Append(GetCopyrightText());
if (sb.Length==sbLength) sb.Append("No Copyright information available.");
response = sb.ToString();
}

break;
default:
//
break;
}
return response;
}

#endregion[/code]
versacexw 2008-12-01
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protected void TitleMenu_DataBound(object sender, EventArgs e)
{
Menu menu = sender as Menu;
if (menu != null)
{
for (int i = 0; i < menu.Items.Count - 1;i++ )
{
menu.Items[i].SeparatorImageUrl = "~/images/separator.gif";
}
}
}

/// <summary>
/// Displays the error page.
/// </summary>
private void callErrorPage(string errorMessage, Exception exception)
{
Session["ErrorMessage"] = errorMessage;
Session["Error"] = exception;
Page.Response.Redirect("ErrorPage.aspx", true);
}

/// <summary>
/// Checks to see if any resources used by the app are local non-pooled
/// </summary>
/// <returns>True if any resources are local non-pooled</returns>
private bool HasNonPooledResources()
{
// define a boolean and set it to false by default... no non-pooled resourceitems
bool hasNonPooledResource = false;
// Now go through all resources and find any non-pooled local resources
MapResourceLocal mapResource = null;
GISDataSourceLocal localDataSource = null;
// First, check the map resourceitems
foreach (MapResourceItem mri in MapResourceManager1.ResourceItems)
{
if (mri != null)
{
mapResource = mri.Resource as MapResourceLocal;
if (mapResource != null)
{
MapResourceLocal localRes = mapResource as MapResourceLocal;
localDataSource = mapResource.DataSource as GISDataSourceLocal;
if (!localDataSource.Connection.IsServerObjectPooled(mapResource.ServerContextInfo.ServerObjectName, "MapServer")) hasNonPooledResource = true;

}
}
}
return hasNonPooledResource;
}

protected void ResourceManager_ResourcesInit(object sender, EventArgs e)
{
if (DesignMode)
return;
ResourceManager manager = sender as ResourceManager;
if (!manager.FailureOnInitialize)
return;
if (manager is MapResourceManager)
{
MapResourceManager mapManager = manager as MapResourceManager;
for (int i = 0; i < mapManager.ResourceItems.Count; i++)
{
MapResourceItem item = mapManager.ResourceItems[i];
if (item != null && item.FailedToInitialize)
{
mapManager.ResourceItems[i] = null;
}
}
}
}

private bool OverviewMapResourceIsValid(OverviewMap ov)
{
bool isValidResource = false;
foreach (MapResourceItem resource in MapResourceManager1.ResourceItems)
{
if (resource != null)
{
if (resource.Name == ov.OverviewMapResource)
isValidResource = true;
}
}
return isValidResource;
}

private bool HasCopyrightText()
{
return (GetCopyrightText().Length > 0);
}



private string GetCopyrightText()
{
System.Text.StringBuilder sb = new System.Text.StringBuilder();
string key = "";
string value = "";
string dataframeValue = "";
int layerId;
foreach (IMapFunctionality mapFunc in Map1.GetFunctionalities())
{
if (mapFunc.Supports("GetCopyrightText"))
{
Dictionary<string, string> crDictionary = mapFunc.GetCopyrightText();
System.Text.StringBuilder sb2 = new System.Text.StringBuilder();
string[] layerIds = null;
string[] layerNames = null;
mapFunc.GetLayers(out layerIds, out layerNames);
foreach (KeyValuePair<string, string> kvPair in crDictionary)
{
key = kvPair.Key;
value = kvPair.Value;
if (value != null && value.Length > 0)
{
if (key != null && key.Length > 0)
{
layerId = Convert.ToInt32(key);
sb2.Append(layerNames[layerId] + ": ");
sb2.Append(value + "<br/>");
}
else
dataframeValue = value;
}
}
//if (sb2.Length > 0) sb.AppendFormat("<div style='font-weight: bold'>{0}:</div><div style='padding: 0px 5px 5px 5px;font-weight: normal;'>{2}<br/>{1}</div>", mapFunc.Resource.Name, sb2.ToString(), dataframeValue);
string layerCopyrights = string.Empty;
if (sb2.Length > 0)
layerCopyrights = sb2.ToString();
if (!string.IsNullOrEmpty(dataframeValue) || !string.IsNullOrEmpty(layerCopyrights))
sb.AppendFormat("<div style='font-weight: bold'>{0}:</div><div style='padding: 0px 5px 5px 5px;font-weight: normal;'>{2}<br/>{1}</div>", mapFunc.Resource.Name, layerCopyrights, dataframeValue);
sb2.Length = 0;
dataframeValue = "";

sb2.Length = 0;
dataframeValue = "";
}
}
return sb.ToString();
}
versacexw 2008-12-01
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恩 是空值 这个值是在哪里初始化的呢？？大家帮忙看一下下面两个页面的代码有哪里不对的呢？？谢谢！！！分不够可以再加分 呵呵

下面是default页面的代码
[code=C#]
using System;
using System.Data;
using System.Data.SqlClient;
using System.Configuration;
using System.Collections;
using System.Collections.Generic;
using System.Collections.Specialized;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using ESRI.ArcGIS.ADF.Web;
using ESRI.ArcGIS.ADF.Web.UI.WebControls;
using ESRI.ArcGIS.ADF.Web.DataSources;
using ESRI.ArcGIS.ADF.Web.DataSources.ArcGISServer;
using ESRI.ArcGIS.ADF.Connection.AGS;
using ESRI.ArcGIS.Server;


public partial class WebMapApplication : System.Web.UI.Page, ICallbackEventHandler
{
MapIdentify identify;

public string m_newLoad = "false";
public string m_closeOutCallback = "";
public string m_copyrightCallback = "";

protected void Page_Load(object sender, EventArgs e)
{
if (!Page.IsCallback && !Page.IsPostBack)
{
if (Map1.MapResourceManager == null || Map1.MapResourceManager.Length == 0)
callErrorPage("No MapResourceManager defined for the map.", null);
if (MapResourceManager1.ResourceItems.Count == 0 || MapResourceManager1.ResourceItems[0] == null)
callErrorPage("The MapResourceManager does not have a valid ResouceItem Definition.", null);

m_newLoad = "true";
Map1.ZoomToFullExtent();
}
m_closeOutCallback = Page.ClientScript.GetCallbackEventReference(Page, "argument", "CloseOutResponse", "context", true);
m_copyrightCallback = Page.ClientScript.GetCallbackEventReference(Page, "argument", "processCallbackResult", "context", true);

// initiate identify class and set link to TaskResults1 for response
identify = new MapIdentify(Map1);
identify.ResultsDisplay = TaskResults1;
identify.NumberDecimals = 4;

FloatingPanel ovPanel = Page.FindControl("OverviewMap_Panel") as FloatingPanel;
if (ovPanel != null)
{
ovPanel.PanelCollapsed += new ESRI.ArcGIS.ADF.Web.UI.WebControls.FloatingPanelCollapseEventHandler(OverviewMap_Panel_PanelCollapsed);
ovPanel.PanelExpanded += new ESRI.ArcGIS.ADF.Web.UI.WebControls.FloatingPanelExpandEventHandler(OverviewMap_Panel_PanelExpanded);
}

}
/// <summary>
/// Handles unhandled exceptions in the page.
/// </summary>
protected void Page_Error(object sender, System.EventArgs e)
{
Exception exception = Server.GetLastError();
Server.ClearError();
callErrorPage("Page_Error", exception);
}


protected void Page_PreRenderComplete(object sender, EventArgs e)
{
// If no tasks have been defined, hide the tasks panel
if (TaskMenu.Items.Count == 0)
Tasks_Menu_Panel.Visible = false;
// check to see if any of the resource items are non-pooled
if (!Page.IsCallback || !Page.IsPostBack)
{
CloseHyperLink.Visible = HasNonPooledResources();
OverviewMap ov = Page.FindControl("OverviewMap1") as OverviewMap;
if (ov!=null && !OverviewMapResourceIsValid(ov))
ov.OverviewMapResource = Map1.PrimaryMapResource;
}
CopyrightTextHolder.Visible = HasCopyrightText();

}

protected void Page_PreInit(object sender, EventArgs e)
{
// Make the overview enabled property match floatingpanel expanded property
FloatingPanel ovPanel = Page.FindControl("OverviewMap_Panel") as FloatingPanel;
if (ovPanel != null)
{
OverviewMap ov = ovPanel.FindControl("OverviewMap1") as OverviewMap;
if (ov != null)
ov.Enabled = ovPanel.Expanded;
}

}




honghu3000 2008-12-01
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exception.message是空值吧
versacexw 2008-12-01
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是下面的错误
exception.System.NullReferenceException.base.base.message未将对象引用设置到对象的实例
exception.message未将对象引用设置到对象的实例
这是什么原因呢？？
谢谢！！！
消失的尘芥 2008-12-01
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你没有引用对象,或则是引用出问题!在看看
yijianxiangde100 2008-12-01
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一般情况下是，为初始化对象造成的了。你在仔细检查一下了。
moluotuo 2008-12-01
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你系统指示的错在哪一行？逐个查一下那一行的对象是否在调用方法之前是否是Null
versacexw 2008-12-01
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有一张截图的错误显示，但是不会贴图，应该怎么贴啊？请大家教我一下，我贴上来大家看了错误可能会清楚些，谢谢！！
java六大必须理解的问题 文档
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