如何使用十進制？

Question

在DataGridView中，我有是Letter Grade，Minimum Letter Grade和Maximum Letter Grade字段（例如Letter Grade = A-，Minimum Letter Grade = 85,00和Maximum Letter Grade = 89,99）

例如，如果我更新Minimum Letter Grade = 85,00到85,99它保存它作爲85,00。

如何更新它酷似85,99？

數據庫中的數據類型Letter Grade Min和Letter Grade Max是DECIMAL(4,2)。

public static void updateGradeRanges(string LetterGrd, double LgMin, double LgMax) 
     try 
     { 
      string cmdText = "UPDATE grade_range SET LG_MIN='" + LgMin + "', LG_MAX='" + LgMax + "' WHERE Letter_Grade='" + LetterGrd + "';"; 
      MySqlCommand cmd = new MySqlCommand(cmdText, DB.Conn); 
      int result = cmd.ExecuteNonQuery(); 

     } 

我送參數，以這樣的函數：

updateGradeRanges(LetterGrade,Convert.ToDouble(txtMinGrade.Text),Convert.ToDouble(txtMaxGrde.Text)); 
<asp:UpdatePanel ID="UpdatePanel1" runat="server" Visible="true"> 
<ContentTemplate> 
    <asp:GridView ID="Grades_GridView" runat="server" BackColor="White" BorderColor="White" 
     BorderStyle="Ridge" BorderWidth="2px" CellPadding="3" CellSpacing="1" 
     GridLines="None" AutoGenerateColumns="False" 
     DataKeyNames="Letter_Grade" 
     onrowcancelingedit="Grades_GridView_RowCancelingEdit" 
     onrowediting="Grades_GridView_RowEditing" 
     onrowupdating="Grades_GridView_RowUpdating" 
     onrowdeleting="Grades_GridView_RowDeleting"> 

     <Columns> 
      <asp:TemplateField HeaderText="Letter Grade" SortExpression="Letter_Grade"> 

       <ItemTemplate> 
        <asp:Label ID="Label1" runat="server" Text='<%# Bind("Letter_Grade") %>'></asp:Label> 
       </ItemTemplate> 
      </asp:TemplateField> 
      <asp:TemplateField HeaderText="Minimum Letter Grade" SortExpression="LG_MIN"> 
       <EditItemTemplate> 
        <asp:TextBox ID="txtMinGrade" runat="server" Text='<%# Bind("LG_MIN") %>'></asp:TextBox> 
       </EditItemTemplate> 

       <ItemTemplate> 
        <asp:Label ID="Label2" runat="server" Text='<%# Bind("LG_MIN") %>'></asp:Label> 
       </ItemTemplate> 
      </asp:TemplateField> 
      <asp:TemplateField HeaderText="Maximum Letter Grade" SortExpression="LG_MAX"> 
       <EditItemTemplate> 
        <asp:TextBox ID="txtMaxGrade" runat="server" Text='<%#Bind("LG_MAX") %>'></asp:TextBox> 
       </EditItemTemplate> 

       <ItemTemplate> 
        <asp:Label ID="Label3" runat="server" Text='<%# Bind("LG_MAX") %>'></asp:Label> 
       </ItemTemplate> 
      </asp:TemplateField> 

      <asp:TemplateField HeaderText="Edit" ShowHeader="False"> 
       <EditItemTemplate> 
        <asp:LinkButton ID="LinkButtonUpdateGrade" runat="server" CommandName="Update" CausesValidation="True"><span class="link_span_small">Update</span></asp:LinkButton>&nbsp; 
       <asp:LinkButton ID="LinkButtonCancelGrade" runat="server" CommandName="Cancel" CausesValidation="True"><span class="link_span_small">Cancel</span></asp:LinkButton> 
       </EditItemTemplate> 

       <ItemTemplate> 
        <asp:ImageButton ID="ImageButtonEditGrade" runat="server" CausesValidation="False" 
         CommandName="Edit" ToolTip="Edit" ImageUrl="~/Images/edit.png" /> 
       </ItemTemplate> 
      </asp:TemplateField> 
      </Columns> 


     <FooterStyle BackColor="#C6C3C6" ForeColor="Black" /> 
     <HeaderStyle BackColor="#4A3C8C" Font-Bold="True" ForeColor="#E7E7FF" /> 
     <PagerStyle BackColor="#C6C3C6" ForeColor="Black" HorizontalAlign="Right" /> 
     <RowStyle BackColor="#DEDFDE" ForeColor="Black" /> 
     <SelectedRowStyle BackColor="#9471DE" Font-Bold="True" ForeColor="White" /> 
     <SortedAscendingCellStyle BackColor="#F1F1F1" /> 
     <SortedAscendingHeaderStyle BackColor="#594B9C" /> 
     <SortedDescendingCellStyle BackColor="#CAC9C9" /> 
     <SortedDescendingHeaderStyle BackColor="#33276A" /> 


    </asp:GridView> 
    </ContentTemplate> 
</asp:UpdatePanel> 

Answer 1

從您的SQL UPDATE語句刪除單引號。