SysUtils.pas单元函数IntToHex函数学习札记

SysUtils.pas单元函数IntToHex函数学习笔记

1.函数原型：

function IntToHex(Value: Integer; Digits: Integer): string;//  FmtStr(Result, '%.*x', [Digits, Value]);asm        CMP     EDX, 32        // Digits < buffer length?        JBE     @A1        XOR     EDX, EDX@A1:    PUSH    ESI        MOV     ESI, ESP        SUB     ESP, 32        PUSH    ECX            // result ptr        MOV     ECX, 16        // base 16     EDX = Digits = field width        CALL    CvtInt        MOV     EDX, ESI        POP     EAX            // result ptr        CALL    System.@LStrFromPCharLen        ADD     ESP, 32        POP     ESIend;function IntToHex(Value: Int64; Digits: Integer): string;//  FmtStr(Result, '%.*x', [Digits, Value]);asm        CMP     EAX, 32        // Digits < buffer length?        JLE     @A1        XOR     EAX, EAX@A1:    PUSH    ESI        MOV     ESI, ESP        SUB     ESP, 32        // 32 chars        MOV     ECX, 16        // base 16        PUSH    EDX            // result ptr        MOV     EDX, EAX       // zero filled field width: 0 for no leading zeros        LEA     EAX, Value;        CALL    CvtInt64        MOV     EDX, ESI        POP     EAX            // result ptr        CALL    System.@LStrFromPCharLen        ADD     ESP, 32        POP     ESIend;