delphi判断字符串是否为纯数字组合

function IsNUM(Vaule:String):boolean; //delphi 判断字符串是否为纯数字组合
var
i:integer;
begin
Vaule:=trim(Vaule); //去空格知
for i:=1 to length(Vaule) do //准备循环
begin
if ( Vaule[i] in ['0'..'9'])  then //如果Vaule的第i个字不道是A-Z或者a-z中的任一个回
begin
result:=true; //返回值 不是
end
else
begin
result:=false; //设置返度回值为 是
exit;
end;
end;
end;

function   IsNum(str:   string):   Boolean;  
  var  
      i:   Integer;  
  begin  
      Result   :=   True;  
      for   i   :=   1   to   Length(str)   do  
          if   not   (str[i]   in   ['0'..'9'])   then  
          begin  
              Result   :=   False;  
              Break;  
          end;  
  end;