用户代码未处理空引用异常 [英] Null reference exception was unhandled by user code
问题描述
帮我查一下错误代码Null引用异常未被用户代码处理
受保护的子lbInsert_Click(ByVal发送者为对象,ByVal e As System.EventArgs )
AccessDataSource1.InsertParameters(Nama)。DefaultValue =
DirectCast(GridView1.FooterRow.FindControl(txtNama),TextBox).Text
AccessDataSource1.InsertParameters(NpwpPemotong)。DefaultValue =
DirectCast(GridView1.FooterRow.FindControl(txtNPWP),TextBox).Text
AccessDataSource1.InsertParameters(NomorBukti)。DefaultValue =
DirectCast(GridView1.FooterRow.FindControl(txtNomorBukti),TextBox).Text < br $>
AccessDataSource1.InsertParameters(TglBuktiPemotong)。DefaultValue =
DirectCast(GridView1.FooterRow.FindControl(txtTglBukti),Calendar)。 SelectedDate <无线电通信/>
AccessDataSource1.InsertParameters(JenisPajak)。DefaultValue =
DirectCast(GridView1.FooterRow.FindControl(ddlInsertJenisPajak),DropDownList).SelectedValue
AccessDataSource1.InsertParameters(JumlahPPH)。DefaultValue =
DirectCast(GridView1.FooterRow.FindControl(txtJumlahPPH),TextBox) .Text
AccessDataSource1.Insert()
结束子
谢谢
我尝试了什么:
空引用异常未被处理用户代码
Hi, help me for the error code Null reference exception was unhandled by user code
Protected Sub lbInsert_Click(ByVal sender As Object, ByVal e As System.EventArgs)
AccessDataSource1.InsertParameters("Nama").DefaultValue =
DirectCast(GridView1.FooterRow.FindControl("txtNama"), TextBox).Text
AccessDataSource1.InsertParameters("NpwpPemotong").DefaultValue =
DirectCast(GridView1.FooterRow.FindControl("txtNPWP"), TextBox).Text
AccessDataSource1.InsertParameters("NomorBukti").DefaultValue =
DirectCast(GridView1.FooterRow.FindControl("txtNomorBukti"), TextBox).Text
AccessDataSource1.InsertParameters("TglBuktiPemotong").DefaultValue =
DirectCast(GridView1.FooterRow.FindControl("txtTglBukti"), Calendar).SelectedDate
AccessDataSource1.InsertParameters("JenisPajak").DefaultValue =
DirectCast(GridView1.FooterRow.FindControl("ddlInsertJenisPajak"), DropDownList).SelectedValue
AccessDataSource1.InsertParameters("JumlahPPH").DefaultValue =
DirectCast(GridView1.FooterRow.FindControl("txtJumlahPPH"), TextBox).Text
AccessDataSource1.Insert()
End Sub
thanks
What I have tried:
Null reference exception was unhandled by user code
推荐答案
我认为您在签署价值之前验证是否存在控件...
I think that you have validate if exists controls before you asigned value...
AccessDataSource1.InsertParameters("Nama").DefaultValue = <pre lang="XML">GridView1.FooterRow.FindControl("txtNama") <> null ?
DirectCast(GridView1.FooterRow.FindControl("txtNama"), TextBox).Text</pre> : ""
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