问题描述
亲爱的朋友当我们在RowDataCommand上计算列值的运行总数时，我有一个名为Geidview1的Gridview它返回错误对象引用未设置为对象的实例
下面是错误的图像
请任何人都可以建议我们如何删除此错误。
以下是我的代码
我的c＃代码用于绑定gridview
public void bindgvduedate（）
{
con = new SqlConnection（）;
con.ConnectionString = ConfigurationManager.ConnectionStrings [con1]。ConnectionString;
con.Open（）;
SqlCommand cmd = new SqlCommand（）;
cmd.CommandText =readfeedetails;
cmd.CommandType = CommandType.StoredProcedure;
cmd.Connection = con;
////cmd.Parameters.AddWithValue(\"@ classname，Convert.ToString（ddlclassname.SelectedItem））;
////cmd.Parameters.AddWithValue(\"@feecatename，Convert.ToString（ddlstcategory.SelectedItem））;
SqlDataAdapter da = new SqlDataAdapter（cmd）;
DataTable table = new DataTable（）;
da.Fill（table ）;
GridView1.DataSource = table;
GridView1.DataBind（）;
con.Close（）;
}
这个函数我在页面加载事件上调用
Griedview aspx代码
< asp：GridView ID =GridView1runat =server AutoGenerateColumns =False
BackColor =WhiteBorderColor =＃336666BorderStyle =Double
字体大小=11pxBorderWidth =3px
CellPadding =4GridLines =both
ShowFooter =Trueonrowdatabound =GridView1_RowDataBound>
< rowstyle forecolor =＃333333backcolor =White height =21px>
< columns>
< asp：TemplateField>
< HeaderTemplate> Apr-15< / HeaderTemplate>
< itemtemplate>< asp：标签ID =lblaprlrunat =serverText ='<％＃Eval（Apr-15）％>'>
< footertemplate> < asp：Label ID =lbl_aprTotalamountCssClass =footer_textrunat =serverText =1>
< asp：TemplateField>
< HeaderTemplate> 5月15日< / HeaderTemplate>
< itemtemplate>< asp：Label ID =lblmayrunat =serverText ='<％＃Eval（May-15）％>'>
< footertemplate> < asp：Label ID =lbl_mayTotalamountCssClass =footer_textrunat =serverText =1>
< asp：TemplateField>
< HeaderTemplate> Jun-15< / HeaderTemplate>
< itemtemplate>< asp：Label ID =lbljunrunat =serverText ='<％＃Eval（Jun-15）％>'>
< footertemplate> < asp：Label ID =lbl_junTotalamountCssClass =footer_textrunat =serverText =1>
< asp：TemplateField>
< HeaderTemplate> Jul-15< / HeaderTemplate>
< itemtemplate>< asp：Label ID =lbljulrunat =serverText ='<％＃Eval（Jul-15）％>'>
< footertemplate> < asp：Label ID =lbl_julTotalamountCssClass =footer_textrunat =serverText =1>
< asp：TemplateField>
< HeaderTemplate> Aug-15< / HeaderTemplate>
< itemtemplate>< asp：Label ID =lblaugrunat =serverText ='<％＃Eval（Aug-15）％>'>
< footertemplate> < asp：Label ID =lbl_augTotalamountCssClass =footer_textrunat =serverText =1>
< asp：TemplateField>
< HeaderTemplate> Sep-15< / HeaderTemplate>
< itemtemplate>< asp：Label ID =lblseprunat =serverText ='<％＃Eval（Sep-15）％>'>
< footertemplate> < asp：Label ID =lbl_sepTotalamountCssClass =footer_textrunat =serverText =1>
< asp：TemplateField>
< HeaderTemplate> 10月15日< / HeaderTemplate>
< itemtemplate>< asp：Label ID =lbloctrunat =serverText ='<％＃Eval（Oct-15）％>'>
< footertemplate> < asp：Label ID =lbl_octTotalamountCssClass =footer_textrunat =serverText =1>
< asp：TemplateField>
< HeaderTemplate> Nov-15< / HeaderTemplate>
< itemtemplate>< asp：Label ID =lblnovrunat =serverText ='<％＃Eval（Nov-15）％>'>
< footertemplate> < asp：Label ID =lbl_novTotalamountCssClass =footer_textrunat =serverText =1>
< asp：TemplateField>
< HeaderTemplate> Dec-15< / HeaderTemplate>
< itemtemplate>< asp：Label ID =lbldecrunat =serverText ='<％＃Eval（Dec-15）％>'>
< footertemplate> < asp：Label ID =lbl_decTotalamountCssClass =footer_textrunat =serverText =1>
< asp：TemplateField>
< HeaderTemplate> Jan-15< / HeaderTemplate>
< itemtemplate>< asp：Label ID =lbljanrunat =serverText ='<％＃Eval（Jan-15）％>'>
< footertemplate> < asp：Label ID =lbl_janTotalamountCssClass =footer_textrunat =serverText =1>
< asp：TemplateField>
< HeaderTemplate> Feb-15< / HeaderTemplate>
< itemtemplate>< asp：Label ID =lblfebrunat =serverText ='<％＃Eval（Feb-15）％>'>
< footertemplate> < asp：Label ID =lbl_febTotalamountCssClass =footer_textrunat =serverText =1>
< asp：TemplateField>
< HeaderTemplate> Mar-15< / HeaderTemplate>
< itemtemplate>< asp：Label ID =lblmarrunat =serverText ='<％＃Eval（Mar-15）％>'>
< footertemplate> < asp：Label ID =lbl_marTotalamountCssClass =footer_textrunat =serverText =1>
< asp：TemplateField>
< HeaderTemplate> Total< / HeaderTemplate>
< itemtemplate>< asp：Label ID =lbltotalrunat =serverText =0>
< footertemplate> < asp：Label ID =lbl_TotalsamountCssClass =footer_textrunat =serverText =1>
< footerstyle backcolor =Whiteforecolor =＃333333>
< pagerstyle backcolor =＃336666forecolor =Whitehorizontalalign =Center>
< SelectedRowStyle BackColor =＃339966Font-Bold =TrueForeColor =White/> ;
< HeaderStyle BackColor =＃336666Font-Bold =TrueForeColor =White/>
计算运行总计的代码
protected void GridView1_RowDataBound（object sender，GridViewRowEventArgs e）
{
if（e.Row.RowType == DataControlRowType.Footer）
{
con = new SqlConnection（）;
con.Connect ionString = ConfigurationManager.ConnectionStrings [con1]。ConnectionString;
con.Open（）;
SqlCommand cmd = new SqlCommand（从dbo中选择sum（feeamount）。 feemaster其中classname ='KG'和feeactive = 1和feecatename ='NEW'和duemonth ='Apr-15'，con）;
SqlDataReader dr = cmd.ExecuteReader（）;
if（dr.Read（））
{
//e.Row.Cells[1].Text =Total：;
标签lbl_aprTotalamount = GridView1.FindControl（lbl_aprTotalamount）作为标签;
lbl_aprTotalamount.Text = dr [0] .ToString（）;
}
}
}
我的数据库表
CREATE TABLE [dbo]。[feemaster]（
[feeId] [int ] IDENTITY（1,1）NOT NULL，
[ footype] [nvarchar]（50）NULL，
[feename] [nvarchar]（50）NULL，
[classname] [nvarchar]（50）NULL，
[duemonth] [nvarchar]（50）NULL，
[feeamount] [decimal]（15,2）NULL，
[feeactive] [ bit] NULL，
[feecatename] [nvarchar]（50）NULL
）ON [PRIMARY]
GO
SET IDENTITY_INSERT [dbo]。[feemaster] ON
INSERT [dbo]。[feemaster]（[feeId]，[footype]，[feename]，[classname]，[duemonth]，[ feeamount]，[feeactive]，[feecatename]）VALUES（1，N'One Time'，N'Prospectus&注册费'，N'PRE NURSURY'，N'Apr-15'，CAST（300.00 AS Decimal（15,2）），1，N'NEW'）
INSERT [dbo]。[ feemaster]（[feeId]，[footype]，[feename]，[classname]，[duemonth]，[feeamount]，[feeactive]，[feecatename]）VALUES（13，N'One Time'，N'Prospectus&注册费'，N'NURSURY'，N'Apr-15'，CAST（300.00 AS Decimal（15,2）），1，N'NEW'）
INSERT [dbo]。[feemaster] ]（[feeId]，[footype]，[feename]，[classname]，[duemonth]，[feeamount]，[feeactive]，[feecatename]）VALUES（2，N'One Time'，N'Prospectus& Registration费'，N'KG'，N'Apr-15'，CAST（300.00 AS十进制（15,2）），1，N'NEW'）
INSERT [dbo]。[feemaster]（[feeId]，[footype]，[feename]，[classname]，[duemonth]，[feeamount]，[feeactive]，[feecatename]）VALUES（16，N'Annual'， N'Maintenance Fee'，N'NURSURY'，N'Apr-15'，CAST（500.00 AS Decimal（15,2）），1，N'NEW'）
INSERT [dbo]。 [feemaster]（[feeId] ，[footype]，[feename]，[classname]，[duemonth]，[feeamount]，[feeactive]，[feecatename]）VALUES（17，N'Annual'，N'Maintenance Fee'，N'NURSURY'，N 'Apr-15'，CAST（500.00 AS Decimal（15,2）），1，N'OLD'）
INSERT [dbo]。[feemaster]（[feeId]，[feetype]， [feename]，[classname]，[duemonth]，[feeamount]，[feeactive]，[feecatename]）VALUES（18，N'Annual'，N'Maintenance Fee'，N'KG'，N'Apr-15' ，CAST（500.00 AS十进制（15,2）），1，N'NEW'）
我的存储过程
创建过程[dbo]。[readfeedetails]
AS
BEGIN
选择
*
来自
（
选择f.feename，f.feeamount ，dd.duemonth
来自feemaster作为f
左外连接duedate为dd在dd.duemonth = f.duemonth，其中classname ='KG'和feeactive = 1和feecatename ='老'
）a sf
pivot
（
min（f.feeamount）
for f.duemonth in（[Apr- 15]，[5月15日]，[6月15日]，[7月15日]，[8月15日]，[9月15日]，[10月15日]，[11月15日]，[12月15日] ，[1月15日]，[2月15日]，[3月15日]）
）作为PIV
END
GO
Dear Friend I have one Gridview with the name Geidview1 when we calculate running total of column values on RowDataCommand Event it return an error "Object reference not set to an instance of an object"
below is the image of error
please any one can suggest us how we can remove this error.
below is my code
my c# code for bind gridview
public void bindgvduedate()
{
con = new SqlConnection();
con.ConnectionString = ConfigurationManager.ConnectionStrings["con1"].ConnectionString;
con.Open();
SqlCommand cmd = new SqlCommand();
cmd.CommandText = "readfeedetails";
cmd.CommandType = CommandType.StoredProcedure;
cmd.Connection = con;
////cmd.Parameters.AddWithValue("@classname",Convert.ToString(ddlclassname.SelectedItem));
////cmd.Parameters.AddWithValue("@feecatename", Convert.ToString(ddlstcategory.SelectedItem));
SqlDataAdapter da = new SqlDataAdapter(cmd);
DataTable table = new DataTable();
da.Fill(table );
GridView1.DataSource= table;
GridView1.DataBind();
con.Close();
}
this function i call on page load event
Griedview aspx code
<asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="False"
BackColor="White" BorderColor="#336666" BorderStyle="Double"
Font-Size="11px" BorderWidth="3px"
CellPadding="4" GridLines="both"
ShowFooter="True" onrowdatabound="GridView1_RowDataBound">
<rowstyle forecolor="#333333" backcolor="White" height="21px">
<columns>
<asp:TemplateField>
<HeaderTemplate>Apr-15 </HeaderTemplate>
<itemtemplate><asp:Label ID="lblaprl" runat="server" Text='<%#Eval("Apr-15") %>'>
<footertemplate> <asp:Label ID="lbl_aprTotalamount" CssClass="footer_text" runat="server" Text="1">
<asp:TemplateField>
<HeaderTemplate>May-15 </HeaderTemplate>
<itemtemplate><asp:Label ID="lblmay" runat="server" Text='<%#Eval("May-15")%>'>
<footertemplate> <asp:Label ID="lbl_mayTotalamount" CssClass="footer_text" runat="server" Text="1">
<asp:TemplateField>
<HeaderTemplate>Jun-15 </HeaderTemplate>
<itemtemplate><asp:Label ID="lbljun" runat="server" Text='<%#Eval("Jun-15") %>'>
<footertemplate> <asp:Label ID="lbl_junTotalamount" CssClass="footer_text" runat="server" Text="1">
<asp:TemplateField>
<HeaderTemplate>Jul-15 </HeaderTemplate>
<itemtemplate><asp:Label ID="lbljul" runat="server" Text='<%#Eval("Jul-15") %>'>
<footertemplate> <asp:Label ID="lbl_julTotalamount" CssClass="footer_text" runat="server" Text="1">
<asp:TemplateField>
<HeaderTemplate>Aug-15 </HeaderTemplate>
<itemtemplate><asp:Label ID="lblaug" runat="server" Text='<%#Eval("Aug-15") %>'>
<footertemplate> <asp:Label ID="lbl_augTotalamount" CssClass="footer_text" runat="server" Text="1">
<asp:TemplateField>
<HeaderTemplate>Sep-15 </HeaderTemplate>
<itemtemplate><asp:Label ID="lblsep" runat="server" Text='<%#Eval("Sep-15") %>'>
<footertemplate> <asp:Label ID="lbl_sepTotalamount" CssClass="footer_text" runat="server" Text="1">
<asp:TemplateField>
<HeaderTemplate>Oct-15 </HeaderTemplate>
<itemtemplate><asp:Label ID="lbloct" runat="server" Text='<%#Eval("Oct-15") %>'>
<footertemplate> <asp:Label ID="lbl_octTotalamount" CssClass="footer_text" runat="server" Text="1">
<asp:TemplateField>
<HeaderTemplate>Nov-15 </HeaderTemplate>
<itemtemplate><asp:Label ID="lblnov" runat="server" Text='<%#Eval("Nov-15") %>'>
<footertemplate> <asp:Label ID="lbl_novTotalamount" CssClass="footer_text" runat="server" Text="1">
<asp:TemplateField>
<HeaderTemplate>Dec-15 </HeaderTemplate>
<itemtemplate><asp:Label ID="lbldec" runat="server" Text='<%#Eval("Dec-15") %>'>
<footertemplate> <asp:Label ID="lbl_decTotalamount" CssClass="footer_text" runat="server" Text="1">
<asp:TemplateField>
<HeaderTemplate>Jan-15 </HeaderTemplate>
<itemtemplate><asp:Label ID="lbljan" runat="server" Text='<%#Eval("Jan-15") %>'>
<footertemplate> <asp:Label ID="lbl_janTotalamount" CssClass="footer_text" runat="server" Text="1">
<asp:TemplateField>
<HeaderTemplate>Feb-15 </HeaderTemplate>
<itemtemplate><asp:Label ID="lblfeb" runat="server" Text='<%#Eval("Feb-15") %>'>
<footertemplate> <asp:Label ID="lbl_febTotalamount" CssClass="footer_text" runat="server" Text="1">
<asp:TemplateField>
<HeaderTemplate>Mar-15 </HeaderTemplate>
<itemtemplate><asp:Label ID="lblmar" runat="server" Text='<%#Eval("Mar-15") %>'>
<footertemplate> <asp:Label ID="lbl_marTotalamount" CssClass="footer_text" runat="server" Text="1">
<asp:TemplateField>
<HeaderTemplate>Total </HeaderTemplate>
<itemtemplate><asp:Label ID="lbltotal" runat="server" Text="0">
<footertemplate> <asp:Label ID="lbl_Totalsamount" CssClass="footer_text" runat="server" Text="1">
<footerstyle backcolor="White" forecolor="#333333">
<pagerstyle backcolor="#336666" forecolor="White" horizontalalign="Center">
<SelectedRowStyle BackColor="#339966" Font-Bold="True" ForeColor="White" />
<HeaderStyle BackColor="#336666" Font-Bold="True" ForeColor="White" />
code for calculating running total
protected void GridView1_RowDataBound(object sender, GridViewRowEventArgs e)
{
if (e.Row.RowType == DataControlRowType.Footer)
{
con = new SqlConnection();
con.ConnectionString = ConfigurationManager.ConnectionStrings["con1"].ConnectionString;
con.Open();
SqlCommand cmd = new SqlCommand("select sum(feeamount) from dbo.feemaster where classname='KG'and feeactive=1 and feecatename='NEW'and duemonth='Apr-15'", con);
SqlDataReader dr = cmd.ExecuteReader();
if (dr.Read())
{
//e.Row.Cells[1].Text = "Total : ";
Label lbl_aprTotalamount = GridView1.FindControl("lbl_aprTotalamount") as Label;
lbl_aprTotalamount.Text = dr[0].ToString();
}
}
}
my database table
CREATE TABLE [dbo].[feemaster](
[feeId] [int] IDENTITY(1,1) NOT NULL,
[feetype] [nvarchar](50) NULL,
[feename] [nvarchar](50) NULL,
[classname] [nvarchar](50) NULL,
[duemonth] [nvarchar](50) NULL,
[feeamount] [decimal](15, 2) NULL,
[feeactive] [bit] NULL,
[feecatename] [nvarchar](50) NULL
) ON [PRIMARY]
GO
SET IDENTITY_INSERT [dbo].[feemaster] ON
INSERT [dbo].[feemaster] ([feeId], [feetype], [feename], [classname], [duemonth], [feeamount], [feeactive], [feecatename]) VALUES (1, N'One Time', N'Prospectus & Registration Fee', N'PRE NURSURY', N'Apr-15', CAST(300.00 AS Decimal(15, 2)), 1, N'NEW')
INSERT [dbo].[feemaster] ([feeId], [feetype], [feename], [classname], [duemonth], [feeamount], [feeactive], [feecatename]) VALUES (13, N'One Time', N'Prospectus & Registration Fee', N'NURSURY', N'Apr-15', CAST(300.00 AS Decimal(15, 2)), 1, N'NEW')
INSERT [dbo].[feemaster] ([feeId], [feetype], [feename], [classname], [duemonth], [feeamount], [feeactive], [feecatename]) VALUES (2, N'One Time', N'Prospectus & Registration Fee', N'KG', N'Apr-15', CAST(300.00 AS Decimal(15, 2)), 1, N'NEW')
INSERT [dbo].[feemaster] ([feeId], [feetype], [feename], [classname], [duemonth], [feeamount], [feeactive], [feecatename]) VALUES (16, N'Annual', N'Maintenance Fee', N'NURSURY', N'Apr-15', CAST(500.00 AS Decimal(15, 2)), 1, N'NEW')
INSERT [dbo].[feemaster] ([feeId], [feetype], [feename], [classname], [duemonth], [feeamount], [feeactive], [feecatename]) VALUES (17, N'Annual', N'Maintenance Fee', N'NURSURY', N'Apr-15', CAST(500.00 AS Decimal(15, 2)), 1, N'OLD')
INSERT [dbo].[feemaster] ([feeId], [feetype], [feename], [classname], [duemonth], [feeamount], [feeactive], [feecatename]) VALUES (18, N'Annual', N'Maintenance Fee', N'KG', N'Apr-15', CAST(500.00 AS Decimal(15, 2)), 1, N'NEW')
my stored procedure
create proc [dbo].[readfeedetails]
AS
BEGIN
select
*
from
(
select f.feename, f.feeamount,dd.duemonth
from feemaster as f
left outer join duedate as dd on dd.duemonth =f.duemonth where classname='KG' and feeactive=1 and feecatename='OLD'
) as f
pivot
(
min(f.feeamount)
for f.duemonth in ([Apr-15],[May-15],[Jun-15],[Jul-15],[Aug-15],[Sep- 15],[Oct-15],[Nov-15],[Dec-15],[Jan-15],[Feb-15],[Mar-15])
) as PIV
END
GO
这篇关于你调用的对象是空的。在RowDataCommand的gridview中的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！