<el-col :span="16">
      <el-input @input="validateInput"  maxlength="7" v-model="inputForm.perfSum" />
</el-col>

 function validateInput(value) {

      let temp = value.toString();
      temp = temp.replace(/。/g, ".");
      temp = temp.replace(/[^\d.]/g, "");
      temp = temp.replace(/^\./g, "");
      temp = temp.replace(/\.{2,}/g, "");
      temp = temp.replace(".", "$#$").replace(/\./g, "").replace("$#$", ".");
      temp = temp.replace(/^(\-)*(\d+)\.(\d\d).*$/, "$1$2.$3");
      inputForm.value.perfSum = temp
  }