ASP.NET自定義驗證程序客戶端和服務器端驗證

Question

在我的網頁中，我試圖在客戶端和服務器端進行預先驗證。如果下拉菜單和文本框爲空，我需要顯示一條錯誤消息，但是如果填寫了其中一個，驗證應該通過。 有沒有辦法爲兩個控件創建一個CustomValidator？我有一種感覺，我做得不對。

客戶端代碼：

<div> 
 
     <table> 
 
      <tr> 
 
       <td> 
 
       <asp:DropDownList ID="ddlStates" runat="server" Width="128px"> 
 
          <asp:ListItem></asp:ListItem> 
 
          <asp:ListItem>Nevada</asp:ListItem> 
 
          <asp:ListItem>Uta</asp:ListItem> 
 
          <asp:ListItem>Oregon</asp:ListItem> 
 
        </asp:DropDownList> 
 
       </td> 
 
       <td> 
 
        <asp:CustomValidator ID="cvddlState" runat="server" 
 
        ClientValidationFunction="StatesCheck" 
 
        OnServerValidate="ServerValidation" 
 
        ErrorMessage="(*) State is required" ForeColor="Red" 
 
        Display="Dynamic"></asp:CustomValidator> 
 
       </td> 
 

 
      </tr> 
 
      <tr> 
 
       <td> 
 
        <asp:TextBox ID="txtStates" runat="server"></asp:TextBox> 
 
       </td> 
 
       <td> 
 
        <asp:CustomValidator ID="cvtxtStates" runat="server" 
 
        ValidateEmptyText="true" 
 
        ClientValidationFunction="StatesCheck" 
 
        OnServerValidate="ServerValidation" 
 
        ControlToValidate="txtStates" 
 
        ErrorMessage="(*) Text cannot be empty" ForeColor="Red" 
 
        Display="Dynamic"></asp:CustomValidator> 
 
       </td> 
 

 
      </tr> 
 
      <tr> 
 
       <td> 
 
         <asp:Button ID="btnSubmit" runat="server" Text="Submit" /> 
 
       </td> 
 
      </tr> 
 
     </table> 
 
    </div> 
 

 
    <div id="divErrorMessage" runat="server" class="alert alert-danger" visible="false"></div> 
 
    
 

 
<script type="text/javascript"> 
 

 
    'Use Strict'; 
 
    function StatesCheck(source, args) { 
 
     var ddlStates = document.getElementById("<%=ddlStates.ClientID%>"); 
 
     var txt = document.getElementById('<%=txtStates.ClientID%>').value; 
 
     var state = ddlStates.options[ddlStates.selectedIndex].value; 
 

 
     if (ddlStates !== null) { 
 
      if ((state === "") && (txt === "")) { 
 
       args.IsValid = false; 
 
      } 
 
      else { 
 
       args.IsValid = true; 
 
      } 
 
     } 
 
    } 
 

 
</script>

服務器端代碼：

Public Sub btnSubmit_Click(sender As Object, e As EventArgs) Handles btnSubmit.Click 
 
     Try 
 
      divErrorMessage.Visible = False 
 
      divErrorMessage.InnerText = "" 
 

 

 
      Dim ddlSelection As String = ddlStates.SelectedItem.Text 
 
      Dim statesText As String = txtStates.Text.Trim() 
 
      If statesText = String.Empty And ddlSelection = String.Empty Then 
 
      Else 
 
       divErrorMessage.Visible = True 
 
       divErrorMessage.InnerText = "(*) Text cannot be empty" 
 
      End If 
 

 
     Catch ex As Exception 
 

 
     End Try 
 
    End Sub 
 

 
    Protected Sub ServerValidation(source As Object, args As ServerValidateEventArgs) 
 
     If (ddlStates.SelectedItem.Text = String.Empty) And (txtStates.Text.Length = 0) Then 
 
      args.IsValid = False 
 
     Else 
 
      args.IsValid = True 
 
     End If 
 

 
    End Sub

Answer 1

你是從兩個代碼上得到答案服務器端和客戶端？我想根據我的expirience回答服務器端

Protected Sub ServerValidation(source As Object, args As ServerValidateEventArgs) 
     If (ddlStates.SelectedItem.Text = String.Empty) And (txtStates.Text.Length = 0) Then 
      args.IsValid = False 
     Else 
      args.IsValid = True 
     End If 

    End Sub 

，林在ASP.net不太好，但基於上述ypur代碼，那裏有什麼錯，不過部分你說but if one of them is filled out the validation should pass犯規節目在這裏可以請你嘗試做這一個。

Protected Sub ServerValidation(source As Object, args As ServerValidateEventArgs) 
      If (ddlStates.SelectedItem.Text = String.Empty) Or (txtStates.Text.Length = 0) Then 
       args.IsValid = False 
Else 
       args.IsValid = True 
      End If 

     End Sub 

也許

Protected Sub ServerValidation(source As Object, args As ServerValidateEventArgs) 
     If (ddlStates.SelectedItem.Text = String.Empty) And (txtStates.Text.Length = 0) Then 
      args.IsValid = False 
     ElseIf (ddlStates.SelectedItem.Text <> String.Empty) then 
      args.IsValid = True 
     ElseIf (txtStates.Text <> "") then 
      args.IsValid = True 
     Else 

      args.IsValid = True 
     End If 

    End Sub 

Answer 2

這是一個片段，您可以用CustomValidator

<asp:CustomValidator ID="CustomValidator1" runat="server" Display="Dynamic" ErrorMessage="input failed" ClientValidationFunction="myFunction"></asp:CustomValidator> 

<script type="text/javascript"> 
    function myFunction(sender, element) { 
     if (document.getElementById("<%= ddlStates.ClientID %>").selectedIndex == 0 && document.getElementById("<%= txtStates.ClientID %>").value != "") { 
      element.IsValid = true; 
     } else { 
      element.IsValid = false; 
     } 
    } 
</script> 

Answer 3

評估這兩個控件可以使用客戶端驗證了上述方案。

<div> 
     <table> 
      <tr> 
       <td> 
        <asp:DropDownList ID="ddlStates" runat="server" Width="128px"> 
         <asp:ListItem></asp:ListItem> 
         <asp:ListItem>Nevada</asp:ListItem> 
         <asp:ListItem>Uta</asp:ListItem> 
         <asp:ListItem>Oregon</asp:ListItem> 
        </asp:DropDownList> 
       </td> 

      </tr> 
      <tr> 
       <td> 
        <asp:TextBox ID="txtStates" runat="server"></asp:TextBox> 
       </td> 


      </tr> 
      <tr> 
       <td> 
        <label id="lbltxtstate" style="display: none;">Please select a state or enter a state.</label> 
        <br /> 
        <asp:Button ID="btnSubmit" runat="server" Text="Submit" OnClientClick="return validateState();" /> 
       </td> 
      </tr> 
     </table> 
    </div> 

    <script type="text/javascript"> 
    function validateState(){ 
      if (($('#<%=ddlStates.ClientID %> option:selected').text() == "") && ($('#<%=txtStates.ClientID %>').val() == "")) { 

      $('#lbltxtstate').attr('style', 'display:block'); 
      $('#lbltxtstate').attr('style', 'color:red'); 
      return false; 
     } 
     else {   
       $('#lbltxtstate').attr('style', 'display:none'); 
       return true; 
     }; 

    } 
    </script>