'number' is not a valid type for an input tag - On my local machine only
This makes no sense.. but as inspired by this answer: https://stackoverflow.com/a/27561096/390501
I updated my Target Framework in Visual Studio to 4.5.1 rather than 4.5 and now the page loads without a parser error!
Use this code to use HTML5 input type:
Use this in .aspx file:
<input type="text" placeholder='0.00' ID="txtNum" runat="server" class="txt/>
Use this in .cs file:
txtNum.Attributes["type"] = "number";
txtNum.Attributes["value"] = "0.00";
txtNum.Attributes["min"] = "0";
txtNum.Attributes["step"] = "0.01";