BlitzMax/Language/Strings

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Strings are used to store sequences of characters.

Strings are actually objects, so can be used where ever an object is expected. Strings provide the following methods:

Method Description
Find:Int( subString:String,startIndex=0 ) Finds first occurrence of a sub string. Returns -1 if subString not found.
FindLast:Int( subString:String,startIndex=0 ) Finds last occurrence of a sub string. Returns -1 if subString not found.
Trim:String() Removes leading and trailing non-printable characters from a string.
Replace:String( subString:String,withString:String ) Replaces all occurrences of subString with withString.
StartsWith:Int( subString:String ) Returns true if string starts with subString.
EndsWith:Int( subString:String ) Returns true if string ends with subString.
Contains:Int( subString:String ) Returns true if string contains subString.
Join:String( bits:String[] ) Joins bits together by inserting this string between each bit.
Split:String[]( separator$[] ) Splits this string into bits delimited by separator.
ToLower:String() Converts string to lowercase.
ToUpper:String() Converts string to uppercase.
ToInt:Int() Converts string to an integer.
ToLong:Long() Converts string to a long.
ToFloat:Float() Converts string to a float.
ToDouble:Double() Converts string to a double.
ToCString:Byte Ptr() Converts string to a null terminated sequence of 8 bit bytes. The returned memory must eventually be freed with a call to MemFree.
ToWString:Short Ptr() Converts string to a null terminated sequence of 16 bit shorts. The returned memory must eventually be freed with a call to MemFree.

Strings also provide a read-only length field. Here is an example of using string methods:

Local t:String="***** HELLO *****"

Print t.length   'return length of string: 17
Print t.Find( "HE" )  'returns index of substring "HE": 6
Print t.Replace( "*","!" ) 'replaces all "*" with "!"
Print t.ToLower()  'coverts string to lowercase
Print ":".Join( ["Hello","World"] ) 'returns "Hello:World"

String also provide the following functions to help with the creation of strings:

Function Description
FromInt:String( value:Int ) Creates a string from an integer.
FromLong:String( value:Long ) Creates a string from a long.
FromFloat:String( value:Float ) Creates a string from a float.
FromDouble:String( value:Double) Creates a string from a double.
FromCString:String( cString:Byte Ptr ) Creates a string from a null terminated sequence of 8 bit bytes.
FromWString:String( wString:Short Ptr ) Creates a string from a null terminated sequence of 16 bit shorts.
FromBytes:String( bytes:Byte Ptr,length ) Creates a string from a sequence of length 8 bit bytes.
FromShorts:String( shorts:Short Ptr,length ) Creates a string from a sequence of length 16 bit shorts.

To call a string function, use: String.Function - for example:

Print String.FromInt( 10 )