js 屏蔽禁止掉浏览器自带的选中、复制、剪切、粘贴功能

1. 屏蔽选中

<script>
    document.onselectstart = function (event) {
        if (window.event) {
            event = window.event;
        }
        try {
            var the = event.srcElement;
            if (!((the.tagName == "INPUT" && the.type.toLowerCase() == "text") || the.tagName == "TEXTAREA")) {
                return false;
            }
            return true;
        } catch (e) {
            return false;
        }
    }
</script>

2. 屏蔽复制

<script>
    document.oncopy = function (event) {
        if (window.event) {
            event = window.event;
        }
        try {
            var the = event.srcElement;
            if (!((the.tagName == "INPUT" && the.type.toLowerCase() == "text") || the.tagName == "TEXTAREA")) {
                return false;
            }
            return true;
        } catch (e) {
            return false;
        }
    }
</script>

3. 屏蔽剪切

<script>
    document.oncut = function (event) {
        if (window.event) {
            event = window.event;
        }
        try {
            var the = event.srcElement;
            if (!((the.tagName == "INPUT" && the.type.toLowerCase() == "text") || the.tagName == "TEXTAREA")) {
                return false;
            }
            return true;
        } catch (e) {
            return false;
        }
    }

4. 屏蔽粘贴

<script>
    document.onpaste = function (event) {
        if (window.event) {
            event = window.event;
        }
        try {
            var the = event.srcElement;
            if (!((the.tagName == "INPUT" && the.type.toLowerCase() == "text") || the.tagName == "TEXTAREA")) {
                return false;
            }
            return true;
        } catch (e) {
            return false;
        }
    }
</script>