Created
June 1, 2019 17:33
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parseToDate
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function getRegexForDateFromat(dateFormat) { | |
var dateValueRegexString = | |
dateFormat.replace(/MM|M|DD|D|YYYY/g, function(match, position, original) { | |
switch (match) { | |
case "M": | |
return "([1-9]||1[0-1])"; | |
break; | |
case "MM": | |
return "(0[1-9]||1[0-1])"; | |
break; | |
case "DD": | |
return "(0[1-9]||[1-2][0-9]||3[0-1])"; | |
break; | |
case "D": | |
return "([1-9]||[1-2][0-9]||3[0-1])"; | |
break; | |
case "YYYY": | |
return "([0-9]{4})"; | |
break; | |
} | |
}); | |
return new RegExp("^" + dateValueRegexString + "$"); | |
} | |
function isValidFormat(dateString, dateFormat) { | |
var r = getRegexForDateFromat(dateFormat); | |
return r.test(dateString); | |
} | |
function parseToDate(dateString, dateFormat) { | |
var isValidDateFormat = isValidFormat(dateString, dateFormat); | |
if(isValidDateFormat) { | |
var dateValues = brakeStringDateForValues(dateString, dateFormat); | |
if(dateValuesAreValidDate(dateValues.year, dateValues.month, dateValues.date)) { | |
return new Date(dateValues.year, dateValues.month, dateValues.date); | |
} | |
} | |
} | |
function dateValuesAreValidDate(year, month, date) { | |
var dateObject = new Date(year, month, date); | |
return !!(dateObject.getFullYear() == year && dateObject.getMonth() == month && dateObject.getDate() == date); | |
} | |
function brakeStringDateForValues(dateString, dateFormat) { | |
var r = getRegexForDateFromat(dateFormat); | |
var datePlaceholdersRegexString = | |
dateFormat.replace(/MM|M|DD|D|YYYY/g, function(match, position, original) { | |
return "(" + match + ")"; | |
}); | |
var formatMatches = dateFormat.match(new RegExp("^" + datePlaceholdersRegexString + "$")); | |
var dateMatches = dateString.match(r); | |
var year; | |
var month; | |
var date; | |
for(var i = 0, length = formatMatches.length; i < length; i++) { | |
var dateMatch = dateMatches[i]; | |
var formatMatch = formatMatches[i]; | |
switch(formatMatch) { | |
case "M": | |
case "MM": | |
month = parseInt(dateMatch) - 1; | |
break; | |
case "D": | |
case "DD": | |
date = parseInt(dateMatch); | |
break; | |
case "YYYY": | |
year = parseInt(dateMatch); | |
break; | |
} | |
} | |
return { year: year, month: month, date: date } | |
} | |
module.exports = function() { | |
return { | |
isValid: isValidFormat, | |
parseToDate: parseToDate | |
}; | |
}; |
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