javascript - Livecycle JavaScript…压缩if语句

我正在处理一个带有“验证”按钮的表单。此按钮的目的是检查并确保所有字段均已填写（这是项目要求的）。下面的代码检查该字段是否为null，然后更改边框颜色并显示一个文本框。

if (form1.Main.sfRequestor.requestNameFirst.rawValue == null){
    form1.Main.sfRequest.txtValidate.presence = "visible";
    form1.Main.sfRequestor.requestNameFirst.border.edge.color.value = "255,0,0"
} else {
    form1.Main.sfRequest.txtValidate.presence = "hidden";
    form1.Main.sfRequestor.requestNameFirst.border.edge.color.value = "255,255,255"
};

if (form1.Main.sfRequestor.requestNameLast.rawValue == null){
    form1.Main.sfRequest.txtValidate.presence = "visible";
    form1.Main.sfRequestor.requestNameLast.border.edge.color.value = "255,0,0"
} else {
    form1.Main.sfRequest.txtValidate.presence = "hidden";
    form1.Main.sfRequestor.requestNameLast.border.edge.color.value = "255,255,255"
};

有几个子表单中有20多个字段需要检查。我正在尝试合并代码，但如何操作却无所适从。变量可以处理Java语言中的字段名称吗？

最佳答案

您可以很容易地使其进入循环，并可以将其编写为IIFE来保持名称空间整洁

(function (arr) {
    var txtValidate = form1.Main.sfRequest.txtValidate,
        i, e;
    for (i = 0; i < arr.length; ++i) {
        e = form1.Main.sfRequestor[arr[i]]; // cache me
        if (e.rawValue == null){
            txtValidate.presence = "visible";
            e.border.edge.color.value = "255,0,0"
        } else {
            txtValidate.presence = "hidden";
            e.border.edge.color.value = "255,255,255"
        }
    }
}(['requestNameFirst', 'requestNameLast']));

但是，看起来txtValidate.presence只能设置为最后一项的条件，您确定不希望使用标志来设置最后一个吗？例如

(function (arr) {
    var txtValidateState = 'hidden',
        i, e;
    for (i = 0; i < arr.length; ++i) {
        e = form1.Main.sfRequestor[arr[i]];
        if (e.rawValue == null){
            txtValidateState = "visible"; // any null makes txtValidate visible
            e.border.edge.color.value = "255,0,0"
        } else {
            e.border.edge.color.value = "255,255,255"
        }
    }
    form1.Main.sfRequest.txtValidate.presence = txtValidateState; // set last
}(['requestNameFirst', 'requestNameLast']));

假设sfRequestor和sfRequest通用形式的更新

(function (form, arr) {
    var txtValidateState = 'hidden',
        i, e;
    for (i = 0; i < arr.length; ++i) {
        e = form.sfRequestor[arr[i]];
        if (e.rawValue == null){
            txtValidateState = "visible";
            e.border.edge.color.value = "255,0,0";
        } else {
            e.border.edge.color.value = "255,255,255";
        }
    }
    form.sfRequest.txtValidate.presence = txtValidateState;
}(form1.Main, ['requestNameFirst', 'requestNameLast']));

假设sfRequest是常量，但sfRequestor可能有所不同

(function () { // moved IIFE to protect namespace
    function validate(form, subform, arr) { // now named, new param subform
        var txtValidateState = 'hidden',
            i, e;
        for (i = 0; i < arr.length; ++i) {
            e = form[subform][arr[i]]; // select from subform
            if (e.rawValue == null){
                txtValidateState = "visible";
                e.border.edge.color.value = "255,0,0";
            } else {
                e.border.edge.color.value = "255,255,255";
            }
        }
        form.sfRequest.txtValidate.presence = txtValidateState; // assuming stays same
    }
    validate(form1.Main, 'sfRequestor', ['requestNameFirst', 'requestNameLast']);
    validate(form1.Main, 'sfClientInfo', ['firstname']);
    // if you have many here you can re-write as a loop again
}());