import Foundation
let pattern = #"(.*),(.*),(.*),(.*)"#
let regex = try! NSRegularExpression(pattern: pattern)
let testString = #"""
,UBS154754528,A121215441,10
,UBS154754528,A121215442,20
,UBS154754528,A121215443,15
GFdfgdfD45454dfgd5457,UBS154754528,A121215444,25
AAA454545455,UBS154754528,A121215445,254
vvGFD454545457,UBS154754528,A121215446,215
dad454545457,UBS154754528,A121215447,55
eww454545457,UBS154754528,A121215448,214
asd454545457,UBS154754528,A121215449,26
trtr454545457,UBS154754528,A121215450,25
,UBS154754528,A121215451,251
,UBS154754528,A121215452,252
,UBS154754528,A121215453,23
,UBS154754528,A121215454,251
gdfgd454545457,UBS154754528,A121215455,251
dfdf454545457,UBS154754528,A121215456,25
fgdfgd454545457,UBS154754528,A121215457,95
gdfgFD45dfg4545457,UBS154754528,A121215458,58
dfgdf4545fg45457,UBS154754528,A121215459,254
dfgd45454dfgfd5457,UBS154754528,A121215460,25
dfdfGFD45dfgdf4545457,UBS154754528,A121215461,254
,UBS154754528,A121215462,66
,UBS154754528,A121215463,22
,UBS154754528,A121215464,54
GfdfgD454fd545457,UBS154754528,A121215465,24
GFfdgD454dfg545457,UBS154754528,A121215466,45
GFfdgD45454fgd5457,UBS154754528,A121215467,11
fgfD4545dfg45457,UBS154754528,A121215468,255
GFfdgD454dfgd545457,UBS154754528,A121215469,88
"""#
let stringRange = NSRange(location: 0, length: testString.utf16.count)
let substitutionString = #"insert into test_table values('$1','$2','$3',$4);"#
let result = regex.stringByReplacingMatches(in: testString, range: stringRange, withTemplate: substitutionString)
print(result)
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Swift 5.2, please visit: https://developer.apple.com/documentation/foundation/nsregularexpression