我发现，对布尔值使用“1”和空值“”比使用“true”或“false”字符串值更有效。。。特别是对于html表单，因为Dom元素中的未初始化/空值将始终求值为false，而其中的任何值都求值为true。

例如：

<input type='button' onclick='this.value = tog(this.value);' />

<script type="text/javascript">

    function tog(off) {
        if(off) {
            alert('true, toggle to false');
            return '';
        } else {
            alert('false, toggle to true');
            return '1';
        }
    }   
</script>

似乎是一条更容易的路，到目前为止，这条路一直很稳定/容易。。。也许有人能找到打破这种局面的方法？

我编写了一个助手函数来处理您的案例（以及其他一些）。根据您的具体需要随意更改

/**
 * @example
 * <code>
 * var pageRequestParams = {'enableFeatureX': 'true'};
 * toBool(pageRequestParams.enableFeatureX);  // returns true
 *
 * toBool(pageRequestParams.enableFeatureY, true, options.enableFeatureY)
 * </code>
 * @param {*}value
 * @param {Boolean}[mapEmptyStringToTrue=false]
 * @param {Boolean}[defaultVal=false] this is returned if value is undefined.
 *
 * @returns {Boolean}
 * @example
 * <code>
 * toBool({'enableFeatureX': ''        }.enableFeatureX);          // false
 * toBool({'enableFeatureX': ''        }.enableFeatureX, true);    // true
 * toBool({                            }.enableFeatureX, true);    // false
 * toBool({'enableFeatureX': 0         }.enableFeatureX);          // false
 * toBool({'enableFeatureX': '0'       }.enableFeatureX);          // false
 * toBool({'enableFeatureX': '0 '      }.enableFeatureX);          // false
 * toBool({'enableFeatureX': 'false'   }.enableFeatureX);          // false
 * toBool({'enableFeatureX': 'falsE '  }.enableFeatureX);          // false
 * toBool({'enableFeatureX': 'no'      }.enableFeatureX);          // false
 *
 * toBool({'enableFeatureX': 1         }.enableFeatureX);          // true
 * toBool({'enableFeatureX': '-2'      }.enableFeatureX);          // true
 * toBool({'enableFeatureX': 'true'    }.enableFeatureX);          // true
 * toBool({'enableFeatureX': 'false_'  }.enableFeatureX);          // true
 * toBool({'enableFeatureX': 'john doe'}.enableFeatureX);          // true
 * </code>
 *
 */
var toBool = function (value, mapEmptyStringToTrue, defaultVal) {
    if (value === undefined) {return Boolean(defaultVal); }
    mapEmptyStringToTrue = mapEmptyStringToTrue !== undefined ? mapEmptyStringToTrue : false; // default to false
    var strFalseValues = ['0', 'false', 'no'].concat(!mapEmptyStringToTrue ? [''] : []);
    if (typeof value === 'string') {
        return (strFalseValues.indexOf(value.toLowerCase().trim()) === -1);
    }
    // value is likely null, boolean, or number
    return Boolean(value);
};

    MyLib.Convert.bool = function(param) {
         var res = String(param).toLowerCase();
         return !(!Boolean(res) || res === "false" || res === "0");
     }; 

将字符串（“true”、“false”）和布尔值转换为布尔值

('' + flag) === "true"

标志可以在哪里

 var flag = true
 var flag = "true"
 var flag = false
 var flag = "false"

我使用这个简单的方法（使用“myVarToTest”）：

var trueValuesRange = ['1', 1, 'true', true];

myVarToTest = (trueValuesRange.indexOf(myVarToTest) >= 0);

木眼要小心。在看到以500+的赞成票获得最高答案后的后果后，我觉得有义务发布一些实际有用的东西：

让我们从最短但非常严格的方式开始：

var str = "true";
var mybool = JSON.parse(str);

以一种恰当、更宽容的方式结束：

var parseBool = function(str, strict) 
{
    // console.log(typeof str);
    // strict: JSON.parse(str)
    
    if (str == null)
    {
        if (strict)
            throw new Error("Parameter 'str' is null or undefined.");

        return false;
    }
    
    if (typeof str === 'boolean')
    {
        return (str === true);
    } 
    
    if(typeof str === 'string')
    {
        if(str == "")
            return false;
            
        str = str.replace(/^\s+|\s+$/g, '');
        if(str.toLowerCase() == 'true' || str.toLowerCase() == 'yes')
            return true;
        
        str = str.replace(/,/g, '.');
        str = str.replace(/^\s*\-\s*/g, '-');
    }
    
    // var isNum = string.match(/^[0-9]+$/) != null;
    // var isNum = /^\d+$/.test(str);
    if(!isNaN(str))
        return (parseFloat(str) != 0);
        
    return false;
}

测试：

var array_1 = new Array(true, 1, "1",-1, "-1", " - 1", "true", "TrUe", "  true  ", "  TrUe", 1/0, "1.5", "1,5", 1.5, 5, -3, -0.1, 0.1, " - 0.1", Infinity, "Infinity", -Infinity, "-Infinity"," - Infinity", " yEs");

var array_2 = new Array(null, "", false, "false", "   false   ", " f alse", "FaLsE", 0, "00", "1/0", 0.0, "0.0", "0,0", "100a", "1 00", " 0 ", 0.0, "0.0", -0.0, "-0.0", " -1a ", "abc");


for(var i =0; i < array_1.length;++i){ console.log("array_1["+i+"] ("+array_1[i]+"): " + parseBool(array_1[i]));}

for(var i =0; i < array_2.length;++i){ console.log("array_2["+i+"] ("+array_2[i]+"): " + parseBool(array_2[i]));}

for(var i =0; i < array_1.length;++i){ console.log(parseBool(array_1[i]));}
for(var i =0; i < array_2.length;++i){ console.log(parseBool(array_2[i]));}