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This time I will bring you JS to determine whether the input is a number and how many decimals to retain. JS to determine whether the input is a number and how many decimals to retain. What are the precautions?. Here is a practical case. One Get up and take a look.
1. Verification method validationNumber(e, num) e represents the label object, num represents the number of decimal places to be retained
function validationNumber(e, num) { var regu = /^[0-9]+\.?[0-9]*$/; if (e.value != "") { if (!regu.test(e.value)) { alert("请输入正确的数字"); e.value = e.value.substring(0, e.value.length - 1); e.focus(); } else { if (num == 0) { if (e.value.indexOf('.') > -1) { e.value = e.value.substring(0, e.value.length - 1); e.focus(); } } if (e.value.indexOf('.') > -1) { if (e.value.split('.')[1].length > num) { e.value = e.value.substring(0, e.value.length - 1); e.focus(); } } } } }
2. Verification integer
<asp:TextBox ID="txtNg" name="txtNg" runat="server" Height="16px" Width="98px" Font-Size="9pt" CssClass="EditTextBox" onpropertychange="validationNumber(this,0)"></asp:TextBox>
3. One digit is reserved Decimal
<asp:TextBox ID="txtChglinecost" name="txtChglinecost" runat="server" Height="16px" Width="98px" Font-Size="9pt" CssClass="EditTextBox" onpropertychange="validationNumber(this,1)"></asp:TextBox>
4. Keep two decimal places
<asp:TextBox ID="txtStdyr" name="txtStdyr" runat="server" Height="16px" Width="98px" Font-Size="9pt" CssClass="EditTextBox" onpropertychange="validationNumber(this,2)"></asp:TextBox>
5. Keep three decimal places
Just put validationNumber(this,3)
in the method Just change the second parameter to 3.
Keep four decimal places, keep five decimal places, and so on...
I believe you have mastered the method after reading the case in this article. For more exciting information, please pay attention to other related articles on the PHP Chinese website !
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