MID

<p style="margin-top:0"><span style="font-size: 8px;font-family:&#39;Arial&#39;,&#39;sans-serif&#39;">&nbsp;</span></p><h3 style="margin-top:5px;margin-right:0;margin-bottom:0;margin-left: 64px;margin-bottom:0"><a></a>1.1.1.1<span style="font:9px &#39;Times New Roman&#39;">&nbsp; </span>MID</h3><p style="margin-top:13px">该函数用于获取源字符串中的一部分字符。输入变量 <span style="font-family:&#39;Arial&#39;,&#39;sans-serif&#39;">STR </span>为 <span style="font-family:&#39;Arial&#39;,&#39;sans-serif&#39;">STRING </span><span style="letter-spacing:-1px">类型，</span><span style="font-family:&#39;Arial&#39;,&#39;sans-serif&#39;;letter-spacing:-1px">LEN</span> 与 <span style="font-family:&#39;Arial&#39;,&#39;sans-serif&#39;">POS </span>为 <span style="font-family:&#39;Arial&#39;,&#39;sans-serif&#39;">INT </span><span style="letter-spacing:-0">类型，返回值为</span> <span style="font-family:&#39;Arial&#39;,&#39;sans-serif&#39;">STRING</span></p><p style="margin-top:2px">类型。</p><p style="margin-top:0"><span style="font-size: 9px;font-family:宋体">&nbsp;</span></p><p><span style="font-family:&#39;Arial&#39;,&#39;sans-serif&#39;">MID (STR, LEN, POS) </span>的意思是：获取字符串 <span style="font-family:&#39;Arial&#39;,&#39;sans-serif&#39;">STR </span>中从第 <span style="font-family:&#39;Arial&#39;,&#39;sans-serif&#39;">POS </span>个字符位置开始，长度为 <span style="font-family:&#39;Arial&#39;,&#39;sans-serif&#39;">LEN </span>的部分字符。</p><p style="margin-top:0"><span style="font-size: 8px;font-family:宋体">&nbsp;</span></p><p><span style="font-family:&#39;Arial&#39;,&#39;sans-serif&#39;">FBD </span>中示例：</p><p style="margin-top:1px"><span style="font-size: 15px;font-family:宋体">&nbsp;</span></p><p style="margin-left:201px;line-height:87px"><img src="/upload/article/20230611/1686449906399331.png" title="1686449906399331.png" alt="image.png"/></p><p style="margin-top:1px"><span style="font-size: 15px;font-family:宋体">&nbsp;</span></p><p><span style="font-family:&#39;Arial&#39;,&#39;sans-serif&#39;">ST </span>中示例：</p><p style="margin-top:0"><span style="font-size: 10px;font-family:宋体">&nbsp;</span></p><p style="margin-top:0;margin-right:7px;margin-bottom:0;margin-left:0;margin-bottom:0;text-align:center"><span style="font-family:&#39;Arial&#39;,&#39;sans-serif&#39;">VarSTRING1 := MID (&#39;SUSI&#39;,2,2);</span></p><p><br/></p>