The lastIndexOf() returns the index of the last occurrence of a substring in a string, or -1 if the string does not contain the substring. It searches for the ... ... <看更多>

You are misunderstanding that particular overload of the LastIndexOf method. The docs state the following: The search starts at a specified ... ... <看更多>

JavaScript 中使用substr、substring、indexOf、lastIndexOf 等擷取字串方式。 substr. substr ( start , length ) 表示從start 位置開始，擷取length ... ... <看更多>

... <看更多>

## S3 method for class 'String' lastIndexOf(this, s, fromIndex=0, ...) Arguments. fromIndex. The index to start the search from. Value. ... <看更多>