A program, landing interface with the image display verification code, verification code generated by the function and map, under some system to display the code

Don't know is a cause or a reason code system, give advice or comments

 procedure GetRandomCheckCode (var img: Timage; Var codeStr: string); 
Const 
ConstStr='0123456789 abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyz'; 
Var 
I, J, K: Integer; 
VPoint: TPoint; 
VLeft: Integer; 
X, Y: Integer; 
VChaos: Integer; 
The begin 
CodeStr:='; 

For J:=1 to 4 do 
The begin 
Randomize. 
0.1 K:=StrToInt (Format (' % d ', [the Random (Length (constStr))))); 
CodeStr:=codeStr + Trim (constStr [K]); 
end; 
If (Length (codeStr)=3) then 
The begin 
Randomize. 
0.1 K:=StrToInt (Format (' % d ', [the Random (Length (constStr))))); 
CodeStr:=codeStr + Trim (constStr [K]); 
end; 

VLeft:=5; 
Img. Picture:=nil; 
{set the background color} 
Img. Canvas. Brush. Color:=$FEEEE2;//clAqua; 
Img. Canvas. FillRect (the Rect (0, 0, img Width, img, Height)); 

For I:=1 to Length (codeStr) do 
The begin 
With img do 
The begin 
VChaos:=100; 
For J:=0 to vChaos do 
The begin 
X:=the Random (img. Width); 
Y:=the Random (img. Height); 
Img. Canvas. Pen. Color:=clOlive; 
Img. Canvas. Pen. Style:=psDot; 
Img. Canvas. Pixels (X, Y) :=RGB ($C0, $C0, $C0); {noise color} 
end; 

Canvas, the Font Size:=the Random (10) + 11; 
Canvas. The Font. Color:=RGB (Random (256) and $C0, Random (256) and $C0, 
Random (256) and $C0); 
Canvas, the Font Style:=[fsBold]; 

Canvas. The Font. The Name:=Screen Fonts [11]. 
VPoint. X:=the Random (4) + vLeft; 
VPoint. Y:=the Random (5); 
Canvas. TextOut (vPoint. X, vPoint. Y, codeStr [I]); 
VLeft:=vPoint. X + Canvas. TextWidth (codeStr [I]); 
end; 
end; 
end; 

CodePudding user response:

0.1 K:=StrToInt (Format (' % d ', [the Random (Length (constStr)))));
This is a little problem! Is may return zero values, then constStr [K]. Can be a problem

CodePudding user response:

CNPACK in this one for reference