javascript input 공백 막기

<input type="input" th:field="*{str}" th:onkeyup="|javascript:fnBlockBlank(this);|" th:onchange="|javascript:fnBlockBlank(this);|"/>

<script type="text/javascript">
    // 공백 체크
    function fnBlockBlank(obj) {
        var str_space = /\s/;
        if(obj.value == "")
        {   
            obj.focus();
            obj.value = 1;
            return false;
        }
    }

 

//가운데 공백 입력 x

function fnBlockBlank(obj) 
{             
    var str_space = /\s/;
    if(str_space.exec(obj.value)) 
    { 
alert("해당 항목에는 공백을 사용할 수 없습니다.\n\n공백 제거됩니다.");
obj.focus();
obj.value = obj.value.replace(' ',''); // 공백제거
return false;
    }
}
</script>