JavaScript string processing

String processing

1. Connection string:

1) connector +:

2) Connection Assignment + =:

3) Connection letter concat ()

2. find sub-string position indexOf()

1) whether a given string exists in the specified string ( first occurrence )

2) Usage str.indexof (SUBSTR);

3) The presence returns a value greater than or equal to 0 ; return -1

3. find the specified position character Chatat (n)

1) search for characters in a specified position in a string

2) Usage str.charat (n);

3) index starting from 0

4. confirm where the substring last appears in the string lastIndexOf()

1) Get the last position of the substring in the string

2) usage var n=str.lastindexof (ARGSTR)

3) The presence returns a value greater than or equal to 0 ; return -1

5. intercept the first substring of a string substring()

1) Gets the first substring of a specified length of a string

2) usage var substr=str.substring (Gegin[,end]);

3) when begin>length-1 , if end>length-1, the interception is an empty string;

4) If the Begin and end values are reasonable and begin>end, begin and End Interchange

5) Difference from substr(start,length)

6. extracting part of a string slice()

1) Extracts a part of the string and returns a new string

2) usage var substr=str.slice (Begin[,end])

3) Difference from substring ( ): when begin>length-1 , the empty string is returned; when begin>end , return empty string

7. splitting a string into a string array split()

1) Divide the string into substrings

2) usage var array=str.split (s);--s as a separator (can be any combination of strings)

JavaScript string processing