Javascript String 字串操作包_javascript技巧

核心代碼:

複製代碼 代碼如下:

/**
* 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.
*（返回字串中某子串出現的次數）
* @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.
*（此函數用來屏蔽或者保留 "inCharList" 中的字元，取決於參數 "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.
*（此函數用來判斷 inString 是否為 inCharList 中的字元，或者進行相反的判斷，取決於參數 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.
*（此函數進行字串的替換功能，將 inSrc 中的 inOld 全部替換為 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.
*（從字串的左面開始去除空白字元）
* @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.
*（與上面的函數相對應，從字串的右側去除空白字元）
* @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().

示範區：

<script> if (typeof jscript == 'undefined') { jscript = function() { } } jscript.string = function() { } 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(). 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(). 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(). 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(). 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(). 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(). jscript.string.fullTrim = function(inStr) { if (inStr == null || inStr == "") { return ""; } inStr = this.leftTrim(inStr); inStr = this.rightTrim(inStr); return inStr; } // End fullTrim(). </script> <div id="jscript_string_div">substrCount()-Count how many times the string "wo" appears in the string "How much wood would a woodchuck chuck if a woodchuck could chuck wood" (5) <br><br>stripChars()-Strip the characters 'aeio' from the string "Denny Crane is cool!", then strip all characters EXCEPT 'DenyCran' <br><br>strContentValid()-Validate that the string "12345" only contains numbers (true), and then that the string "abc123" does not contain the character b (false) <br><br>replace()-Replace "wood" with "metal" in the string "How much wood would a woodchuck chuck if a woodchuck could chuck wood" <br><br>leftTrim()-Trim leading spaces from the string "  test" (will display length before (6) and after (4) <br><br>rightTrim()-Trim trailing spaces from the string "test  " (will display length before (6) and after (4)) <br><br>fullTrim()-Trim both leading and trailing spaces from the string "  test  " (will display length before (8) and after (4)) <br><br>breakLine()-Break up the string "All work and no play makes Homer go crazy" into 10 character chunks <br><br></div> <div id="c_jquery_test" ></div>
[Ctrl+A 全選 注:如需引入外部Js需重新整理才能執行]