提供一个 JS String 包,包含了一些常用的对字符串操作的函数,详细的请看源码及演示
核心代码: 复制代码 代码如下: /** * jscript.string package * This package contains utility functions for working with strings. */ if (typeof jscript == 'undefined') { jscript = function() { } } jscript.string = function() { } /** * This function searches a string for another string and returns a count * of how many times the second string appears in the first. *(返回字符串中某子串出现的次数) * @param inStr The string to be searched. * @param inSearchStr The string to search for. * @return The number of times inSearchStr appears in inStr, * or 0 if inStr or inSearchStr is null or a blank string. */ jscript.string.substrCount = function(inStr, inSearchStr) { if (inStr == null || inStr == "" || inSearchStr == null || inSearchStr == "") { return 0; } var splitChars = inStr.split(inSearchStr); return splitChars.length - 1; } // End substrCount(). /** * This function will take take an input string and either strip any * character that appears in a given list of characters, or will strip any * character that does NOT appear in a given list of characters. *(此函数用来屏蔽或者保留 "inCharList" 中的字符,取决于参数 "inStripOrAllow") * @param inStr The string to strip characters. * @param inStripOrAllow Either the value "strip" or "allow". * @param inCharList This is either (a) the list of characters that * will be stripped from inStr (when inStripOrAllow == * "strip"), or (b) the list of characters that will * NOT be stripped from inStr (when inStripOrAllow == "allow". * @return The value of inStr after characters have been * stripped as specified. */ jscript.string.stripChars = function(inStr, inStripOrAllow, inCharList) { if (inStr == null || inStr == "" || inCharList == null || inCharList == "" || inStripOrAllow == null || inStripOrAllow == "") { return ""; } inStripOrAllow = inStripOrAllow.toLowerCase(); var outStr = ""; var i; var j; var nextChar; var keepChar; for (i = 0; i < inStr.length; i++) { nextChar = inStr.substr(i, 1); if (inStripOrAllow == "allow") { keepChar = false; } else { keepChar = true; } for (j = 0; j < inCharList.length; j++) { checkChar = inCharList.substr(j, 1); if (inStripOrAllow == "allow" && nextChar == checkChar) { keepChar = true; } if (inStripOrAllow == "strip" && nextChar == checkChar) { keepChar = false; } } if (keepChar == true) { outStr = outStr + nextChar; } } return outStr; } // End stripChars(). /** * This function can check is a given string either only contains characters * from a list, or does not contain any characters from a given list. *(此函数用来判断 inString 是否为 inCharList 中的字符,或者进行相反的判断,取决于参数 inFromExcept) * @param inString The string to validate. * @param inCharList A list of characters that is either (a) the only * characters allowed in inString (when inFromExcept * is == "from_list") or (b) the only characters that * cannot appear in inString (when inFromExcept is * == "not_from_list"). * @param inFromExcept When this is "from_list", then inString may only * contain characters from inCharList. When this is * "not_from_list", then inString can contain any character * except thos in inCharList. * @return True if inString only contains valid characters, * as listed in inCharList when inFromExcept == * "from_list", false if not, or true if inString does * not containt any of the characters listed in * inCharList when inFromExcept == "not_from_list". */ jscript.string.strContentValid = function(inString, inCharList, inFromExcept) { if (inString == null || inCharList == null || inFromExcept == null || inString == "" || inCharList == "") { return false; } inFromExcept = inFromExcept.toLowerCase(); var i; if (inFromExcept == "from_list") { for (i = 0; i < inString.length; i++) { if (inCharList.indexOf(inString.charAt(i)) == -1) { return false; } } return true; } if (inFromExcept == "not_from_list") { for (i = 0; i < inString.length; i++) { if (inCharList.indexOf(inString.charAt(i)) != -1) { return false; } } return true; } } // End strContentValid(). /** * This function replaces a given substring of a string (all occurances of * it to be more precise) with a specified new substring. The substrings * can of course be single characters. *(此函数进行字符串的替换功能,将 inSrc 中的 inOld 全部替换为 inNew) * @param inSrc The string to replace substring(s) in. * @param inOld The substring to replace. * @param inNew The new substring to insert. * @return The value of inSrc with all occurances of inOld replaced * with inNew. */ jscript.string.replace = function(inSrc, inOld, inNew) { if (inSrc == null || inSrc == "" || inOld == null || inOld == "" || inNew == null || inNew == "") { return ""; } while (inSrc.indexOf(inOld) > -1) { inSrc = inSrc.replace(inOld, inNew); } return inSrc; } // End replace(). /** * Function to trim whitespace from the beginning of a string. *(从字符串的左面开始去除空白字符) * @param inStr The string to trim. * @return The trimmed string, or null if null or a blank string was * passed in. */ jscript.string.leftTrim = function(inStr) { if (inStr == null || inStr == "") { return null; } var j; for (j = 0; inStr.charAt(j) == " "; j++) { } return inStr.substring(j, inStr.length); } // End leftTrim(). /** * Function to trim whitespace from the end of a string. *(与上面的函数相对应,从字符串的右侧去除空白字符) * @param inStr The string to trim. * @return The trimmed string, or null if null or a blank string was * passed in. */ jscript.string.rightTrim = function(inStr) { if (inStr == null || inStr == "") { return null; } var j; for (j = inStr.length - 1; inStr.charAt(j) == " "; j--) { } return inStr.substring(0, j + 1); } // End rightTrim(). /** * Function to trim whitespace from both ends of a string. * * @param inStr The string to trim. * @return The trimmed string, or null if null or a blank string was * passed in. */ jscript.string.fullTrim = function(inStr) { if (inStr == null || inStr == "") { return ""; } inStr = this.leftTrim(inStr); inStr = this.rightTrim(inStr); return inStr; } // End fullTrim().