显示相互依赖的验证消息

Question

我在aspx页面中有如下代码：

                <TABLE id="tblGeneratedTo" cellspacing="0" cellpadding="0" width="100%" align="left" border="0" runat="server">
                    <TR>
                        <td width="20%" align="left"><FONT face="Verdana" size="2"><strong>To:</strong></FONT>&nbsp;</TD>
                        <td width="80%">
                            <asp:textbox id="txtGeneratedTo" runat="server" CssClass="ptinput" MaxLength="10" Width="90px"></asp:textbox>
                            <A onclick="window.open('../calPopUp.aspx?textbox=txtGeneratedTo','cal','width=230,height=190,left=400,top=200')"
                                href="javascript:;"> <IMG src="../images/SmallCalendar.gif" border="0"></A> <FONT class="fontbody">
                                (mm/dd/yyyy)</FONT>
                        </TD>               
                    </TR>
                    <tr>
                        <td colspan="2" align="right">
                            <asp:RegularExpressionValidator ID="Regularexpressionvalidator4" runat="server" CssClass="fontbody"
                                Display="Dynamic" ErrorMessage="*Date should be in (mm/dd/yyyy) format." 
                                ValidationExpression="^([\d]{1,2}/[\d]{1,2}/[\d]{4})$"
                                ControlToValidate="txtGeneratedTo"></asp:RegularExpressionValidator>
                            <asp:CompareValidator ID="CompareValidator6" runat="server" CssClass="fontbody" 
                                Display="Dynamic" ErrorMessage="'End' date cannot fall before 'Start' date."
                                ControlToValidate="txtGeneratedTo" Type="Date" Operator="GreaterThanEqual" 
                                ControlToCompare="txtGeneratedFrom"></asp:CompareValidator>
                        </td>
                    </tr>
                </TABLE>

收件人： (月/日/年)
在这里，我有一个文本框和两个验证控件，即。当我在文本框中输入一些垃圾值时，正则表达式并在实际页面上进行比较我一次看到两条消息：

我想一次只看到一条消息。如果满足正则表达式验证器，则最好显示 comparevalidator 消息，否则仅显示正则表达式验证器。

如何做到这一点？如果我们可以仅从 MarkUp 而不是代码隐藏为此做一些事情，那将很容易。

Answer 1

为此，您必须使用 CustomValidator。验证者

<asp:CustomValidator ID="CompareDateValidator" runat="server" 
        ClientValidationFunction="CompareDateValidatorClient"
        ErrorMessage="Some error message" />

伴随此的ClientValidationFunction

function CompareDateValidatorClient(sender, args) {
    var fromValue = document.getElementById('<%=txtGeneratedFrom.ClientID%>').value;
    var toValue = document.getElementById('<%=txtGeneratedTo.ClientID%>').value;
    var isValid = false;
    if (ValidateDate(fromValue)) {
        if (ValidateDate(toValue)) {
            if (Date.parse(toValue) > Date.parse(fromValue)) {
                isValid = true;
            }
            else
                sender.innerHTML = "'End' date cannot fall before 'Start' date.";
        }
        else
            sender.innerHTML = "To date should be in (mm/dd/yyyy) format.";
    }
    else
        sender.innerHTML = "From date should be in (mm/dd/yyyy) format.";
    args.IsValid = isValid;
}

function ValidateDate(str) {

    var rm_date = /^(0[1-9]|1[012])[- /.](0[1-9]|[12][0-9]|3[01])[- /.](19|20)\d\d$/;
    //triple check for not empty, mm/dd/yyyy format and whether the date is valid
    return (str.trim() !== "" && str.match(rm_date) && !isNaN(Date.parse(str)));
}

//remedial javascript. trim function
if (!String.prototype.trim) {
    String.prototype.trim = function () {
        return this.replace(/^\s*(\S*(?:\s+\S+)*)\s*$/, "$1");
    };
}

// ControlToValidate property supports hooking up single element. 
//The below hack hooks both txtGeneratedFrom and txtGeneratedTo to the validator
var validatorObj = document.getElementById("<%= CompareDateValidator.ClientID %>");
ValidatorHookupControlID("<%= txtGeneratedFrom.ClientID %>", validatorObj);
ValidatorHookupControlID("<%= txtGeneratedTo.ClientID %>", validatorObj);