Numeric Values

Question

User-797751191 posted

Hi

  I have below line and want that it should accept only Numeric Values >= 0

<div class="form-group col-md-4 has-error">
<label>Amount *</label>
<asp:TextBox ID="txtAmount" runat="server" class="form-control"  placeholder="Enter Amount" ></asp:TextBox>
</div>

Thanks

Answer 1

User1120430333 posted

What you can do is write a little JavaScript function that takes the data from the control and validates that the data is all numeric data, do an Alert box, and set focus back to the control if not numeric. You would execute the function on the control's Onblur() event.

https://www.mkyong.com/javascript/check-if-variable-is-a-number-in-javascript/

https://www.w3schools.com/jsref/event_onblur.asp

https://www.w3schools.com/jsref/met_html_focus.asp

Answer 2

User475983607 posted

Hi

  I have below line and want that it should accept only Numeric Values >= 0

<div class="form-group col-md-4 has-error">
<label>Amount *</label>
<asp:TextBox ID="txtAmount" runat="server" class="form-control"  placeholder="Enter Amount" ></asp:TextBox>
</div>

Thanks

This problem has been solved long ago using standard Validation Server Controls found in the Visual Studio Toolbox View.

https://blogs.msdn.microsoft.com/codefx/2009/09/08/how-to-use-the-asp-net-validation-control-to-validate-the-user-input/

Answer 3

User288213138 posted

Hi jsshivalik,

You can use RegularExpressionValidator control to validate whether the value of an associated input control matches the pattern specified by a regular expression.

The code:

<div class="form-group col-md-4 has-error">
            <label>Amount *</label>
            <asp:TextBox ID="txtAmount" runat="server" class="form-control" placeholder="Enter Amount"></asp:TextBox>

            <asp:RegularExpressionValidator ID="Regex1" runat="server" ValidationExpression="^([1-9]\d*(\.\d+)?|0)$"
                ErrorMessage="Please enter >=0 value."
                ControlToValidate="txtAmount" />
        </div>

Best regards,

Sam