'Hi Vinny here is how you have to do. Trap the KeyPress event.
' Do not accept any characters other than numerals or operators.. you can include text if you want
Private Sub TextBox1_KeyPress(ByVal KeyAscii As MSForms.ReturnInteger)
Dim myStr As String
If 48 > KeyAscii < 57 Then ' numbers
' Accept the character
ElseIf KeyAscii = 42 Then ' * character
' move the str for later processing
myStr = TextBox1.Text
TextBox1.Text = "+"
ElseIf KeyAscii = 43 Then '+
ElseIf KeyAscii = 45 Then '-
ElseIf KeyAscii = 47 Then '/
ElseIf KeyAscii = 61 Then '= char
' process the result
' do the operation and show it on screen
Else
' Cancel the text box entry
End If
End Sub
Here you have the ascci codes
Asc Value
1
2
3
4
5
6
7
8
9 " "
10 "
"
11
12
13 "
"
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33 !
34 "
35 #
36 $
37 %
38 &
39
40 (
41 )
42 *
43 +
44 ,
45 -
46 .
47 /
48 0
49 1
50 2
51 3
52 4
53 5
54 6
55 7
56 8
57 9
58 :
59 ;
60 <
61 =
62 >
63 ?
64 @
65 A
66 B
67 C
68 D
69 E
70 F
71 G
72 H
73 I
74 J
75 K
76 L
77 M
78 N
79 O
80 P
81 Q
82 R
83 S
84 T
85 U
86 V
87 W
88 X
89 Y
90 Z
91 [
92 93 ]
94 ^
95 _
96 `
97 a
98 b
99 c
100 d
101 e
102 f
103 g
104 h
105 i
106 j
107 k
108 l
109 m
110 n
111 o
112 p
113 q
114 r
115 s
116 t
117 u
118 v
119 w
120 x
121 y
122 z
123 {
124 |
125 }
126 ~
127
128 â¬
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161 ¡
162 ¢
163 £
164 ¤
165 ¥
166 ¦
167 §
168 ¨
169 ©
170 ª
171 «
172 ¬
173 Â
174 ®
175 ¯
176 °
177 ±
178 ²
179 ³
180 ´
181 µ
182 ¶
183 ·
184 ¸
185 ¹
186 º
187 »
188 ¼
189 ½
190 ¾
191 ¿
192 Ã
193 Ã
194 Ã
195 Ã
196 Ã
197 Ã
198 Ã
199 Ã
200 Ã
201 Ã
202 Ã
203 Ã
204 Ã
205 Ã
206 Ã
207 Ã
208 Ã
209 Ã
210 Ã
211 Ã
212 Ã
213 Ã
214 Ã
215 Ã
216 Ã
217 Ã
218 Ã
219 Ã
220 Ã
221 Ã
222 Ã
223 Ã
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253 ý
254 þ
255 ÿ
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