在GridView中获取异常
本文关键字：异常 获取 GridView | 更新日期: 2023-09-27 18:26:05
我使用了GridView控件，在更新（LinkButton）时执行代码。我使用了ObjectDataSource。我是个初学者。所以请解释一下。
正在获取错误-现在得到这个错误-参数化查询"（@pname varchar（7），@pgender varchar（8000），@pcity varchar（8），@pid"需要参数"@pgender"，但没有提供。–
这是背后的代码-
public static int UpdateEmployee(int id, string name, string gender, string city)
{
string connection = "Data Source=SRM-318;Initial Catalog=employee;User ID=sa;Password=****";
SqlConnection scon = new SqlConnection(connection);
string updateQuery = "update emp SET name=@pname, gender=@pgender, city=@pcity WHERE id=@pid";
SqlCommand scmd = new SqlCommand(updateQuery, scon);
scmd.CommandType = CommandType.Text;
scmd.Parameters.Add("@pname", SqlDbType.VarChar).Value = name;
scmd.Parameters.Add("@pgender", SqlDbType.VarChar).Value = gender;
scmd.Parameters.Add("@pcity", SqlDbType.VarChar).Value = city;
scmd.Parameters.Add("@pid", SqlDbType.Int).Value = id;
scon.Open();
return scmd.ExecuteNonQuery();
}
参见设计页面代码-
<body>
<form id="form1" runat="server">
<div>
<asp:GridView ID="GridView1" runat="server" AllowPaging="True" AutoGenerateColumns="False"
BackColor="White" BorderColor="#999999" BorderStyle="None" BorderWidth="1px"
CellPadding="3" DataKeyNames="id" DataSourceID="ObjectDataSource1" ShowFooter="True"
GridLines="Vertical" >
<RowStyle BackColor="#EEEEEE" ForeColor="#8C4510" />
<Columns>
<asp:TemplateField ShowHeader="False">
<ItemTemplate>
<asp:LinkButton ID="LinkButton1" runat="server" CausesValidation="False" CommandName="Edit"
Text="Edit"></asp:LinkButton>
<asp:LinkButton ID="LinkButton2" runat="server" CausesValidation="False" CommandName="Delete"
Text="Delete"></asp:LinkButton>
</ItemTemplate>
<EditItemTemplate>
<asp:LinkButton ID="LinkButton1" runat="server" CausesValidation="True" CommandName="Update"
Text="Update"></asp:LinkButton>
<asp:LinkButton ID="LinkButton2" runat="server" CausesValidation="False" CommandName="Cancel"
Text="Cancel"></asp:LinkButton>
</EditItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="id" SortExpression="id">
<ItemTemplate>
<asp:Label ID="Label1" runat="server" Text='<%# Bind("id") %>'></asp:Label>
</ItemTemplate>
<EditItemTemplate>
<asp:Label ID="Label1" runat="server" Text='<%# Eval("id") %>'></asp:Label>
</EditItemTemplate>
<FooterTemplate>
<asp:LinkButton ID="lb" OnClick="lb_Click" ValidationGroup="INSERT" runat="server">Insert</asp:LinkButton>
</FooterTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="name" SortExpression="name">
<ItemTemplate>
<asp:Label ID="Label2" runat="server" Text='<%# Bind("name") %>'></asp:Label>
</ItemTemplate>
<EditItemTemplate>
<asp:TextBox ID="TextBox1" runat="server" Text='<%# Bind("name") %>'></asp:TextBox>
<asp:RequiredFieldValidator ID="rfvEditName" ControlToValidate="TextBox1" runat="server"
Text="*" ErrorMessage="Name is Required" ForeColor="Red"></asp:RequiredFieldValidator>
</EditItemTemplate>
<FooterTemplate>
<asp:TextBox ID="tbname" runat="server"></asp:TextBox>
<asp:RequiredFieldValidator ID="rfvInsertName" ValidationGroup="INSERT" ControlToValidate="tbname"
runat="server" Text="*" ErrorMessage="Name is Required" ForeColor="Red"></asp:RequiredFieldValidator>
</FooterTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="gender" SortExpression="gender">
<ItemTemplate>
<asp:Label ID="Label3" runat="server" Text='<%# Bind("gender") %>'></asp:Label>
</ItemTemplate>
<EditItemTemplate>
<asp:DropDownList ID="DropDownList1" runat="server">
<asp:ListItem>Select Gender</asp:ListItem>
<asp:ListItem>Male</asp:ListItem>
<asp:ListItem>Female</asp:ListItem>
</asp:DropDownList>
<asp:RequiredFieldValidator ID="rfvEditGender" ControlToValidate="DropDownList1"
runat="server" Text="*" ErrorMessage="Gender is Required" ForeColor="Red" InitialValue="Select Gender"></asp:RequiredFieldValidator>
</EditItemTemplate>
<FooterTemplate>
<asp:DropDownList ID="DropDownList2" runat="server">
<asp:ListItem>Select Gender</asp:ListItem>
<asp:ListItem>Male</asp:ListItem>
<asp:ListItem>Female</asp:ListItem>
</asp:DropDownList>
<asp:RequiredFieldValidator ID="rfvInsertGender" ValidationGroup="INSERT" ControlToValidate="DropDownList2"
runat="server" Text="*" ErrorMessage="Gender is Required" ForeColor="Red" InitialValue="Select Gender"></asp:RequiredFieldValidator>
</FooterTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="city" SortExpression="city">
<ItemTemplate>
<asp:Label ID="Label4" runat="server" Text='<%# Bind("city") %>'></asp:Label>
</ItemTemplate>
<EditItemTemplate>
<asp:TextBox ID="TextBox3" runat="server" Text='<%# Bind("city") %>'></asp:TextBox>
<asp:RequiredFieldValidator ID="rfvEditCity" ControlToValidate="TextBox3" runat="server"
Text="*" ErrorMessage="City is Required" ForeColor="Red"></asp:RequiredFieldValidator>
</EditItemTemplate>
<FooterTemplate>
<asp:TextBox ID="tbcity" runat="server"></asp:TextBox>
<asp:RequiredFieldValidator ID="rfvInsertCity" ValidationGroup="INSERT" ControlToValidate="tbcity"
runat="server" Text="*" ErrorMessage="City is Required" ForeColor="Red"></asp:RequiredFieldValidator>
</FooterTemplate>
</asp:TemplateField>
</Columns>
<FooterStyle BackColor="#CCCCCC" ForeColor="#8C4510" />
<PagerStyle ForeColor="#8C4510" HorizontalAlign="Center" BackColor="#999999" />
<SelectedRowStyle BackColor="#008A8C" Font-Bold="True" ForeColor="White" />
<HeaderStyle BackColor="#000084" Font-Bold="True" ForeColor="White" />
<AlternatingRowStyle BackColor="#DCDCDC" />
</asp:GridView>
<asp:ValidationSummary ValidationGroup="INSERT" ID="ValidationSummary1" ForeColor="Red"
runat="server" />
<asp:ValidationSummary ID="ForGridViewValidations" runat="server" />
<br />
<asp:ObjectDataSource ID="ObjectDataSource1" runat="server"
InsertMethod="InsertEmployee" SelectMethod="GetAllEmployee" TypeName="EmployeeDataAccessLayer"
UpdateMethod="UpdateEmployee" DeleteMethod="DeleteEmployee">
<DeleteParameters>
<asp:Parameter Name="id" Type="Int32" />
</DeleteParameters>
<UpdateParameters>
<asp:Parameter Name="id" Type="Int32" />
<asp:Parameter Name="name" Type="String" />
<asp:Parameter Name="gender" Type="String" />
<asp:Parameter Name="city" Type="String" />
</UpdateParameters>
<InsertParameters>
<asp:Parameter Name="name" Type="String" />
<asp:Parameter Name="gender" Type="String" />
<asp:Parameter Name="city" Type="String" />
</InsertParameters>
</asp:ObjectDataSource>
</div>
</form>
您应该添加sqlCommand参数。
ccmd.Parameters.AddWithValue("@name", value of name);
ccmd.Parameters.AddWithValue("@city", value of city);
ccmd.Parameters.AddWithValue("@gender", value of gender);
ccmd.Parameters.AddWithValue("@id", value of id);
您没有将参数name、gender、city和id传递给您的命令。
它应该是类似的东西
scmd.Parameters.Add["@name", SqlDbType.VarChar];
scmd.Parameters["@name"].Value = name;
依此类推
应该是这样的：
public static int UpdateEmployee(int id, string name, string gender, string city)
{
string connection = "Data Source=SRM-318;Initial Catalog=employee;User ID=sa;Password=****";
SqlConnection scon = new SqlConnection(connection);
string updateQuery = "update emp SET name=@pname, gender=@pgender, city=@pcity WHERE id=@pid";
SqlCommand scmd = new SqlCommand(updateQuery, scon);
scmd.CommandType = CommandType.Text;
scmd.Parameters.Add("@pname", SqlDbType.VarChar).Value = name;
// Edit Starts
if (!String.IsNullOrEmpty(gender))
{
scmd.Parameters.Add("@pgender", SqlDbType.VarChar).Value = gender;
}
else
{
scmd.Parameters.Add("@pgender", SqlDbType.VarChar).Value = DBNull.Value;
}
// Edit Ends
scmd.Parameters.Add("@pcity", SqlDbType.VarChar).Value = city;
scmd.Parameters.Add("@pid", SqlDbType.Int).Value = id;
scon.Open();
return scmd.ExecuteNonQuery();
}