how to set a value of a textbox from javascript function without submitting the page. RSS

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  harimena

  Member

  7 Points

  26 Posts

  how to set a value of a textbox from javascript function without submitting the page.

  Nov 05, 2008 08:23 PM|LINK

  I have a simple javascript function in aspx page. I would like to validate a required field.

  If the textbox was empty, then set the errormesssage_textbox value to "Patient number is required."

   

  HELP!!!!!

   <script type="text/javascript" language="javascript">

  function fnshowalert()

  {

  var flgSubmit=true;

  var pat_errbox='<%=txt_pat_errbox%>'

  var pat_AccountNo = '<%=txt_pat_AccountNo.ClientID%>';

  var val_pat_AccountNo = document.getElementById(pat_AccountNo).value;

  var val_errbox=document.getElementById('<%=txt_pat_errbox%>').value;

   

  if(val_pat_AccountNo.trim()=="")

  {

  //alert("Patient Number Has to be Entered.");

  val_errbox=val_errbox + "Patient Number Has to be Entered."

  flgSubmit=false;

  }

  else

  {

  flgSubmit=true;

  }

  return flgSubmit;

  }

  </script>

  javascript script javascript validations in asp.net javascript validation javascript server-side client-side page methods webmethod scriptmethod

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  ameenkpn

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  Re: how to set a value of a textbox from javascript function without submitting the page.

  Nov 06, 2008 01:01 AM|LINK

  Do like this.
  
   <script>
        
  function fnValidate()
  {
      if (document.getElementById('<%=TextBox1.ClientID%>').value=="")
      {
          document.getElementById('<%=TextBox1.ClientID%>').value ="Patient Number Has to be Entered.";
          return false;
      }
     
      return true;
     
  }
  
      </script>
     
      <asp:TextBox ID="TextBox1" runat="server"></asp:TextBox>
     <asp:Button ID="Button1" runat="server" Text="Button" OnClientClick="return fnValidate();"></asp:Button>
  
  Marking a Reply as 'Answered', not only GAIN us some POINTS, but it also HELP others to find RIGHT solution.
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  harimena

  Member

  7 Points

  26 Posts

  Re: how to set a value of a textbox from javascript function without submitting the page.

  Nov 06, 2008 02:30 PM|LINK

  Hi Ameenkpn,

  I tried the way you said, Its still giving me some err: Microsoft JScript runtime error: 'document.getElementById(...)' is null or not an object

  this is how i tried. Am i missing something still??? FYI: i am using the script tags under <Content> tags, because am using a content page (subpage of a master page).

  function fnValidate()

  {

  var flgSubmit=true;

  //var pat_errbox='<%=txt_pat_errbox.ClientID%>';

  var pat_AccountNo = '<%=txt_pat_AccountNo.ClientID%>';

  var val_pat_AccountNo = document.getElementById(pat_AccountNo).value;

  //var val_errbox=document.getElementById(pat_errbox).value;

   

  if(val_pat_AccountNo.trim()=="")

  {

  //alert("Patient Number Has to be Entered.");

  //val_errbox=val_errbox + "Patient Number Has to be Entered."

  document.getElementById('<%=txt_pat_errbox.ClientID%>').value="Patient Number Has to be Entered." //          --->>>   Error occurs in this line.

  flgSubmit=false;

  }

  else

  {

  flgSubmit=true;

  }

  return flgSubmit;

  }

  </script>

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  NC01

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  Re: how to set a value of a textbox from javascript function without submitting the page.

  Nov 06, 2008 05:43 PM|LINK

  Try:

  var textBoxId = '<%= ((TextBox)Page.Master.FindControl("TextBox1")).ClientID %>';

  NC...
  

• • Reply
  

  harimena

  Member

  7 Points

  26 Posts

  Re: how to set a value of a textbox from javascript function without submitting the page.

  Nov 06, 2008 05:57 PM|LINK

  now its a diff error. What do i do?

  
  Compiler Error Message: BC30108: 'TextBox' is a type and cannot be used as an expression.
  
  Source Error:
  
  

  Line 20: //val_errbox=val_errbox + "Patient Number Has to be Entered." Line 21: //document.getElementById('<%=txt_pat_errbox.ClientID%>').value="Patient Number Has to be Entered." //val_errbox Line 22: document.getElementById('<%= ((TextBox)Page.Master.FindControl("txt_pat_errbox")).ClientID %>').value="Patient Number Has to be Entered." Line 23: flgSubmit=false; Line 24: }

  document.getElementById javascript validation

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  NC01

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  Re: how to set a value of a textbox from javascript function without submitting the page.

  Nov 06, 2008 06:12 PM|LINK

  I don't know because it works for me. Are you sure that you have a Master Page? Are you sure that "txt_pat_errbox" is correct?
  Try: var textBoxId = '<%= ((TextBox)Page.FindControl("TextBox1")).ClientID %>';

  If you still can't fix the error, do a View Source in your browser, look for the TextBox, and post the ID here.

  NC...

   

• • Reply
  

  harimena

  Member

  7 Points

  26 Posts

  Re: how to set a value of a textbox from javascript function without submitting the page.

  Nov 06, 2008 07:38 PM|LINK

  Nc.., here was the interesting part in my code.

  The error occured because the control was visibly false.(in aspx page), hence it was'nt able to find the control and triggered an error.

  Now, when i tried the same code with txt_pat_errbox visible="true" i am able to get what i wanted. that is.. when i clicked submit button, the patientno textbox was checked for null value and error text was shown in txt_pat_errbox right away.

  mm.. but i actually want the same box with error message , visible, only when there is (atleast 1) error.

  i tried this before setting txtbox value:

  document.getElementById('<%=txt_pat_errbox.ClientID%>').visible="True"             ---------------------------->>>>>>> but again same problem, it could'nt detect this control with visible=false.

  document.getElementById('<%=txt_pat_errbox.ClientID%>').value = "Patient Number Has to be Entered."; //val_errbox

  flgSubmit=false;

   ...

  <asp:Panel ID="pnl_pat_errbox" runat="server" Visible="false">

  <asp:TextBox ID="txt_pat_errbox" BackColor="Transparent" BorderStyle="None" CssClass="smallredtext" TextMode="MultiLine" Rows="10" runat="server" Height="185" Width="280" Text=""></asp:TextBox>

  </asp:Panel>

  WHAT NEXT..........???

  thanks NC..you have been giving me wonderful suggestions.

   

  java script validations

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  NC01

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  Re: how to set a value of a textbox from javascript function without submitting the page.

  Nov 07, 2008 11:34 AM|LINK

  Server-side:
       Hide: yourControl.Style.Add("display", "none")
       Show: yourControl.Style.Add("display", "")

  Client-side:
       Hide: document.getElementById('<%= yourControl.ClientID %>').style.display = 'none'
       Show: document.getElementById('<%= yourControl.ClientID %>').style.display = ''

  You can also use "block" or "inline" to show the element, but they produce different effects, so experiment around with them.

  NC...
  

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  harimena

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  26 Posts

  Re: how to set a value of a textbox from javascript function without submitting the page.

  Nov 07, 2008 02:36 PM|LINK

  Thanks Very much. I got this worked Now.[:)]