s1=Text. Text
s2=" "
For i=1 To Len(s1)
ch=Mid(s1,i,1)
If ch>="A" And ch<="Z" Then
'提示:“A”的ASCII码值为65,“a”的ASCII码值为97
End If
s2=s2 & ch
Next i
Text2. Text =s2
要使程序实现上述功能,则方框中的代码是( )。
A.ch=Chr(Asc(ch)+32) |
B.ch=Asc(Chr(ch)+32) |
C.ch=Chr(Asc(ch)-32) |
D.ch=Str(Val(ch)-32) |

同类型试题

y = sin x, x∈R, y∈[–1,1],周期为2π,函数图像以 x = (π/2) + kπ 为对称轴
y = arcsin x, x∈[–1,1], y∈[–π/2,π/2]
sin x = 0 ←→ arcsin x = 0
sin x = 1/2 ←→ arcsin x = π/6
sin x = √2/2 ←→ arcsin x = π/4
sin x = 1 ←→ arcsin x = π/2


y = sin x, x∈R, y∈[–1,1],周期为2π,函数图像以 x = (π/2) + kπ 为对称轴
y = arcsin x, x∈[–1,1], y∈[–π/2,π/2]
sin x = 0 ←→ arcsin x = 0
sin x = 1/2 ←→ arcsin x = π/6
sin x = √2/2 ←→ arcsin x = π/4
sin x = 1 ←→ arcsin x = π/2

