如何限制输入文本以输入使用指令的字母数字字符

Question

 Hi friends I am new in angular Js I want to restrict the input text to enter the          alpha Numeric. how can we achieve this without using any directive.please help

<input type="text" id="number" name="number" class="large" maxlength="5">

我想限制在此文本框中输入字母数字值。