function mailIns(){

        if( document.mailForm.name.value.length == 0){
            
            alert('請輸入姓名！');
            document.mailForm.name.focus();
            return false;    
                        
        } 

        if( document.mailForm.phone.value.length == 0){
            
            alert('請輸入聯絡電話！');
            document.mailForm.phone.focus();
            return false;    
                        
        } 

        if( ! isEmail( document.mailForm.email.value)){
            
            alert('Email 格式有誤！');
            document.mailForm.email.focus();
            return false;  
            
        }

        if( document.mailForm.subject.value.length == 0){
            
            alert('請輸入主旨！');
            document.mailForm.subject.focus();
            return false;    
                        
        }    

        if( document.mailForm.content.value.length == 0){
            
            alert('請輸入內容！');
            document.mailForm.content.focus();
            return false;    
                        
        }  
    
    }