javascript - How to validate the summation of textboxes values in the client side -

if have group of textboxes group 1 , , group of textboxes group 2 .both of them in edit template of grid view want validate the summation of first group equal summation of second group in client side allow save or add .

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ex:

txt1  txt2  txt3 txt4 

i want validate :

   decimal.parse(txt1.text)+ decimal.parse(txt2.text) = decimal.parse(txt3.text )+ decimal.parse(txt4.text) 

note:

one or more of these text boxes may empty , in case consider value 0

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how thing using asp.net validators .

you can use customvalidators. https://msdn.microsoft.com/en-us/library/system.web.ui.webcontrols.customvalidator.aspx

below little example started. can expand mycustomvalidation include checking non-integer values, min-max ranges etc.

    <asp:textbox id="textbox1" runat="server" validationgroup="mygroup"></asp:textbox>     <br />     <asp:textbox id="textbox2" runat="server" validationgroup="mygroup"></asp:textbox>     <br />     <asp:textbox id="textbox3" runat="server" validationgroup="mygroup"></asp:textbox>     <br />     <asp:textbox id="textbox4" runat="server" validationgroup="mygroup"></asp:textbox>     <br /><br />     <asp:button id="button1" runat="server" text="button" validationgroup="mygroup" />     <br />     <asp:customvalidator id="customvalidator1" runat="server" errormessage="error adding textbox values" validationgroup="mygroup" clientvalidationfunction="mycustomvalidation"></asp:customvalidator>      <script type="text/javascript">         function mycustomvalidation(osrc, args) {             var tb1 = document.getelementbyid('<%=textbox1.clientid %>').value;             var tb2 = document.getelementbyid('<%=textbox2.clientid %>').value;             var tb3 = document.getelementbyid('<%=textbox3.clientid %>').value;             var tb4 = document.getelementbyid('<%=textbox4.clientid %>').value;              if (tb1 == "" || tb2 == "" || tb3 == "" || tb4 == "") {                 //to make sure validator fires if 1 or more textboxes left empty                 args.isvalid = false;             } else if (((tb1 + tb2) == (tb3 + tb4))) {                 args.isvalid = true;             } else {                 args.isvalid = false;             }         }     </script>