istGanzZahl neu in matheunit.pas

1 files changed, 12 insertions, 0 deletions

diff --git a/matheunit.pas b/matheunit.pas
index 710a46b..ed9244f 100644
--- a/matheunit.pas
+++ b/matheunit.pas
@@ -39,6 +39,7 @@ function cmpStr(s1,s2: string): longint;
 function mitte(s1,s2: string): string;
 function myFloatToStr(x: extended): string;
 function myStrToFloat(s: string): extended;
+function istGanzZahl(s: string): boolean;
 procedure copyArray(i: tExtPointArray; out o: tExtPointArray); overload;
 procedure copyArray(i: tLongintArray; out o: tLongintArray); overload;
 procedure copyArray(i: tExtendedArray; out o: tExtendedArray); overload;
@@ -321,6 +322,17 @@ begin
    result:=-result;
 end;
 
+function istGanzZahl(s: string): boolean;
+var
+  i:              longint;
+begin
+  result:=length(s)>0;
+  result:=result and (length(s) > byte(s[1] in ['-','+']));
+  if result then
+    for i:=byte(s[1] in ['-','+'])+1 to length(s) do
+      result:=result and (s[i] in ['0'..'9']);
+end;
+
 procedure copyArray(i: tExtPointArray; out o: tExtPointArray);
 var
   j: longint;