RegularExpressionValidator decimal

User Control RegularExpressionValidator with number and decimal regex
Try this regex -
\d{1,}\.?\d{0,}

put to e.g. ValidationExpression="\d{1,}\.?\d{0,}"
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<asp:RegularExpressionValidator ID="RegularExpressionValidator1" runat="server" ControlToValidate="txtWeight"

ErrorMessage="Format(X.XX)" ValidationExpression="\d{1,}\.?\d{0,}"></asp:RegularExpressionValidator>

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