alert 引号问题

string ProcessName = "aaa ";

string messageStr = " <script language= 'javascript '> alert( ' " + ProcessName + " 阶段信息 ! '); </script> ";

this.Page.ClientScript.RegisterStartupScript(this.GetType(), "OpenWindow ", messageStr);

弹出的内容 是 aaa 阶段信息 !
怎样弹出的内容 是 ‘aaa’ 阶段信息 !



------解决方案--------------------
string messageStr = " <script language= 'javascript '> alert(\ " ' " + ProcessName + " ' 阶段信息 !\ "); </script> ";