regex - Getting Index of First Non Alpha character in a string C# -

i'm trying split out string (at index) whenever find first non alpha or whitespace.

my regex rusty , trying find direction on getting work.

example: "payments received 08/14/2015 $0.00" string. , i'm able find first digit

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string alphabet = string.empty; string digit = string.empty; int digitstartindex;  match regexmatch = regex.match("payments received 08/14/2015 $0.00", "\\d");  digitstartindex = regexmatch.index; alphabet = line.substring(0, digitstartindex); digit = line.substring(digitstartindex); 

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the problem lies when string "amount period + $57.00" end "amount period + $"

how using regex in c#, if want include specific non-alphanumeric characters check such $ + -?

edit: i'm looking output (variables alphabet , digit) in example above i'm struggling be.
"amount period"
"+ $57.00"

to split string way mention, use regular expression find initial alpha/space chars , rest.

var s = "payments received 08/14/2015 $0.00"; var re = new regex("^([a-z ]+)(.+)", regexoptions.ignorecase); var m = re.match(s); if (m.success) {     console.writeline(m.groups[1]);     console.writeline(m.groups[2]); } 

the ^ important find characters @ start.