Delphi是数字

Question

Delphi中有没有一种方法可以检查字符串是否为数字而不引发异常？

用于 int 解析。

如果使用

则会引发异常

try
  StrToInt(s);
except
  //exception handling
end;

Answer 1

功能TryStrToInt (const S:字符串；输出值:整数): bool 值；

TryStrToInt converts the string S, which represents an integer-type number in either decimal or hexadecimal notation, into a number, which is assigned to Value. If S does not represent a valid number, TryStrToInt returns false; otherwise TryStrToInt returns true.

To accept decimal but not hexadecimal values in the input string, you may use code like this:

function TryDecimalStrToInt( const S: string; out Value: Integer): Boolean;
begin
   result := ( pos( '$', S ) = 0 ) and TryStrToInt( S, Value );
end;