='b'){/** * Get the substring of a string * @param {integer} start where to start the substring * @param {integer} length how many characters to return * @return {string} */String.prototype.substr=function(substr){returnfunction(start,length){// call the original methodreturnsubstr.cal...
Let's take a look at an example of how to use the substr() method in JavaScript. For example: var totn_string = 'TechOnTheNet'; console.log(totn_string.substr(0,4)); console.log(totn_string.substr(4,2)); console.log(totn_string.substr(6,3)); console.log(totn_string.substr...
http://www.w3school.com.cn/js/jsref_substr.asp -- http://hi.baidu.com/dingyongli/blog/item/f7e6bf09114626276a60fb46.html
The substr() method does not change the original string.To extract characters from the end of the string, use a negative start position.Warning The substr() method is removed (deprecated) in the latest JavaScript standard. Use substring() or slice() instead....
In JavaScript, both the substr() and substring() methods are used to extract substrings from a given string. However, they differ in how they operate and handle certain scenarios: substr() Method The substr() method extracts a portion of a string based on the starting index and a ...
lengthOptional. The number of characters to include in the returned substring. Iflengthis zero or negative, an empty string is returned. If not specified, the substring continues to the end ofstringvar. The following example illustrates the use of thesubstrmethod: ...
*/String.prototype.substr=function(substr) {returnfunction(start, length) {// call the original methodreturnsubstr.call(this,// did we get a negative start, calculate how much it is from the beginning of the string// adjust the start parameter for negative valuestart <0?this.length+ start...
length : 要用来提取的字符数 注意:如果start 是负数,substr 使用它作为从字符串的末尾字符索引 返回值: substr方法返回基于给定参数的新的子字符串 例子: JavaScript String substr() Method var str = "Apples are round, and apples are juicy."; document.write("(1...
js中substring与substr 使用方法 substring 解决方案用于提取字符串中介于两个指定下标之间的字符 substring(start,end) 开始和结束的位置,从零开始的索引 参数 描述 start 必需。一个非负的整数,规定要提取的子串的第一个字符在 stringObject 中的位置。
The substr() method extracts a part of a string. The substr() method begins at a specified position, and returns a specified number of characters. The substr() method does not change the original string. To extract characters from the end of the string, use a negative start position. Se...