angularjs输入框不允许输入空格

html部分代码：

<figure class="pwd_wrap main_wrap" ng-show="change_pwd_window">
    <figcaption>
        <strong>修改密码strong>
        <i class="fa fa-times" aria-hidden="true" ng-click="change_pwd_window=false">i>
    figcaption>
    <div>
        <form class="form-horizontal change_pwd_wrap" name="pwd_frm" method="post" novalidate autocomplete="off">
            <div class="form-body">
                <div class="pwd_item">
                    <label class="title">账号:label>
                    <div class="value">
                        <input type="text" class="form-control" readonly="readonly" ng-model="user_name">
                    div>
                div>

                <div class="pwd_item">
                    <label class="title">原密码:label>
                    <div class="value">
                        <input type="password" ng-keyup="NoSapceInput($event,'old_pwd')" class="form-control" ng-model="old_pwd" />
                    div>
                div>
                <div class="pwd_item">
                    <label class="title">新密码:label>
                    <div class="value">
                        <input type="password"  ng-keyup="NoSapceInput($event,'new_pwd')" name="new_pwd" class="form-control" ng-model="new_pwd" ng-minlength="6" ng-maxlength="18" required/>
                    div>
                div>
                <div class="field-message valid_pwd" ng-messages="pwd_frm.new_pwd.$error" ng-if='pwd_frm.new_pwd.$touched&&pwd_frm.new_pwd.$dirty'
                    ng-cloak>
                    <div ng-message="required">密码是必须的div>
                    <div ng-message="minlength">密码长度必须不少于6div>
                    <div ng-message="maxlength">密码长度必须不大于18div>
                div>
                <div class="pwd_item">
                    <label class="title">确认密码:label>
                    <div class="value">
                        <input type="password" class="form-control" ng-keyup="NoSapceInput($event,'confirm_pwd')" ng-model="confirm_pwd">
                    div>
                div>
                <div class="pwd_item">
                    <button ng-click="save_pwd()" ng-disabled="pwd_frm.$invalid">确认button>
                    <button data-dismiss="modal" ng-click="change_pwd_window=false">取消button>
                div>
            div>
        form>
    div>
figure>

js部分代码：

    //禁止输入空格
    function Trim(str, is_global) {
        var result;
        result = str.replace(/(^\s+)|(\s+$)/g, "");
        if (is_global.toLowerCase() == "g") {
            result = result.replace(/\s/g, "");
        }
        return result;
    }
    $scope.NoSapceInput = function (e,input_name) {
        var curValue = e.target.value;
        $scope[input_name] = curValue;
        $scope[input_name] = Trim(curValue, "g"); 
        console.log($scope[input_name]);
        var keynum;
        if (window.event) // IE 
        {
            keynum = e.keyCode
        }
        else if (e.which) // Netscape/Firefox/Opera 
        {
            keynum = e.which
        }
        if (keynum == 32) {
            return false;
        }
        return true;
    }